She’s one of my earlier childhood ponies, so there’s a lot of nostalgia attached:)

Since the Rainbow Curl Ponies had such extreme curls, they tend to get frizzy/rough hair more frequently.  The curls get tangled easily, and they can get completely matted, much more so than most other ponies.  Brushing out extremely tangled/matted hair can damage it, so these ponies, and the Candy Cane Ponies(they have the same kind of curls) tend to have frizzy hair. 

It’s hard to completely fix. You can use conditioner(the kind you can wash out) on them.  That might help.  It’s hard to de-frizz these ponies completely.  Re-curling the hair can hide the frizz. It’s difficult to restore these curls, but it’ll probably hide most of the damage.  The most common technique is to use plastic straws as curlers, and to dip the hair in boiling water briefly to set the curls.  There are tutorials online if you look.

I generally avoid using products that are left on ponies.  It’s hard to tell what will cause new issues in old ponies, especially a few years down the line.  There is restoration information and resources online.  A lot of people here will be able to give you advice on what to use and what to avoid using on your ponies.

This is a known issue with all the Sparkle Ponies. There seems to be two different  batches of plastic for these.  One discolors badly, the other one doesn’t. The discoloration can be severe. There are even ponies that have both types of plastic on the same pony.  It’s not uncommon to see a Sparkle pony where the head is discolored while the body is not, or vice versa. This issue is found in every pony from the set.  They all come in an undiscolored and a discolored “version”.  The same is true of the Mail Order versions. 

I once had a Sugarberry who looked so bad, she went straight into my bait bin as soon as I got her.  She was dirty in a way that made me not want to touch her. Sticky. Brown. Just disgusting. I thought she had to be discolored as nasty as she was.  Her hair was a matted rat’s nest.  She got chucked into the bait bin, and sat there for years. 

I was cleaning all my trade ponies ahead of a ponymeet I hosted, and I was giving every one at least a quick scrub.  I scrubbed that Sugarberry up, gave her a hair wash/conditioning, and scrunched her hair up a bit to dry.

She turned out just stepped off the card mint.  Perfect hair. Bright white. Absolutely incredible pony.  She went from a bait pony that made me want to use gloves to my mint collection pony with just a wash.

A lot of things factor into what ponies I go after. 
1) I do have a completionist streak, so I sometimes go after the last ones I need for a set.  I don’t collect every set(I’m not a fan of boy ponies, those monster Newborns, or the Sweetheart Sister line, and Dream Beauties are too much expense and hassle), but I usually fill in any holes in any set that I start collecting.

2) I like the theme/symbol. I’m a fan of summer ponies, rabbits, and celestial things, so I’ll usually go for those.

3) They’re just pretty to me.

4) I hate to say it, but failing at getting something often pushes it right to the top of the wantlist.  I lose an auction, I miss an opportunity to get something, or I have a hard time finding one to buy - it quite often becomes my #1 thing to get.  It can take something I’m lukewarm on and turn it into an obsession.

5) There’s something weird or funny about it. A lot of things I didn’t like at first, but they grew on me caught my eye because of this reason(Dance ‘n Prance, that UK Mummy pony that gives birth, Fancy Pants babies, etc).

6) Nostalgia.

As for what makes me not go after something - Cost is a big factor.  I do have some heavy hitters in my collection, but I do draw the line at some of the really big ticket ponies(Takara and South African in particular).  Space issues factor in(I’m less inclined to go after larger items since I don’t have space).  Don’t like boy ponies, any generation.

I have a massive collection and a massive pile of trade stuff.  I also have a tiny house, so a lot of stuff gets packed away in bins. When I get new stuff in, I often have to disassemble large chunks of my closet to get at the bins to check things over/put things away.  This leads to “sort” bins full of random stuff that’s in a kind of limbo between confirmed “processed” collection and confirmed trade. This whole situation has caused problems with keeping things straight.  Big problems.

I have issues with figuring out what is going on all the time.  I’ve sold collection pieces accidentally for cheap because I got them confused with worse condition trade pieces. I’ve accidentally re-bought the same pony multiple times.  I’ve gotten collection pieces mixed into the trade bin more times than I want to think about. I’ve passed on items that I found out later I really needed because I thought I had one already. I even found my a large chunk of my collection ponywear(including multiple items from my childhood) in my trade bin. I still have no idea how that happened.  I think some of my childhood ponies got mixed into the trade bin too, but I’m still not sure how many or which ones.  I’m still missing a few ponies. It’s a real problem. 

It’s taken years, but I have made great strides in organizing things.  I now have a binder which lists what I have, and where to find it, and I do try to update it regularly.  I’m religious about labeling “sort bin” items, so no more mystery bags of ponies and/or accessories. I’ve started labeling collection items(including accessory bags), and I even made up tags that have spaces for the date I got it, where I got it, and other information.   I’ve developed a color coded system for labeling bins so there is no confusion between collection and trade bins, and I have tried to store the bins in separate areas of the house to really keep them apart. It’s still a work in progress,  but is has reduced a lot of the costly mistakes. It’s not entirely eliminated them, but it has reduced them significantly.

One of my best purchases was a BIN on ebay for $275 + $8 shipping.  I can’t remember everything that I got, but it had Ice Crystal, the entire uk/euro flower pony set, all three Colorswirls, the set of UK/euro Playtime babies, multiple other UK/Euro ponies(or UK/Euro versions), 5 MIB ponies(including a Baby Brother pony and the entire USA Apple Delight family, and I think one or two UK/Euro babies), a MIB original 80s Halloween mask/smock costume, about 50-70 loose common ponies, and about a dozen MIP Totsy outfits. The seller sent it Priority mail for only $8.  She taped multiple Priority boxes together into one 4 foot column of ponies.  I’m sure she lost money on shipping, even at 1999-2000 prices.  Even back then, that was an absolute steal at $275. 

I also got a High Flying Beauty Glider for 50 cents at a thrift store.  Absolutely lovely condition. Completely intact, barely any paint damage, even pink hair!

I also got a *mint* TAF Yum Yum at a collectible toy store for $6. She was just fell off the card mint - perfectly white, bubblegum pink hair - the works!  I found a mint porcelain  “Magical Kingdom”(the castle one) for $25 at the same toy store a few years later.

I found a Glow ‘n Show Starglow for $7 at an antique mall a few years ago too.

I think G1’s peak was 2-4 years in.  They were everywhere, and everyone I knew had at least one, even my friends who didn’t have many toys. I remember seeing Surprise and Sparkler hanging on pegs in the grocery store.  I think part of the reason they’re so common was the incredible availability, but also there weren’t as many possible ponies to get in those early years.  If you found a pony for sale in a store, it was one of a smaller pool of possible characters.

After the movie, there was a massive diversification of the line.  Instead of just a few different sets to collect, there were dozens.  All that product takes up space, and only the biggest toy retailers could hope to carry all of them.  Because of this, smaller retailers would have to pick and choose which sets to order, so distribution started to get complicated.   

Also, the first few years had mostly simple, single ponies that came with a ribbon, comb, and (usually) a sticker on a plain backcard.  They were around $5 almost everywhere, so they were just in the impulse buy range for most people.  Later on they started adding in more accessories, coming in boxes, and the price started to creep up.

This pattern seems to have repeated itself for every generation, and as a general rule the last few years of a generation have usually had the rarest ponies.