This is what I would advise, if you are intending to sell regularly. I've been doing it for a year both on etsy and ebay and there are advantages to both. So let me see if I can tell you what I do, maybe you will get some ideas
1. I have a deviantart account to post my work in [any gallery would work though that gets a lot of exposure].
2. I have a facebook artist account that I update with all my dolls and ponies, and I try to network with other groups and members that are interested in the same things I am. I also join groups on facebook where I can post links to my auctions for people interested.
3. I put my low cost sales items in my etsy store [or my commission slots], because they list for three months per listing, and the fee is very minimal when you sell, unlike ebay who kind of screws you a little unless you sell high [the percentage they take goes down the higher the price you get for your item]
4. I post here as well in the appropriate categories when I list new items.
5. You are right, don't list too many items at once. As it is I have ah ard time getting ten items out at once so if nothing else, stagger your listings a few days, in groups, so you can keep up more easily.
6. When you list on ebay OR etsy, connect all of your other medias to it. Post in your gallery a link to the auction, on facebook groups or your page post your links to auctions, etc etc etc. It's all about networking. It takes a while to build up a reputation and to get a decent price for your items. I namely only put customs on ebay when I need fast money, OR I know it will be something that will sell for a good amount. On etsy you of course set the fee so can't have bidding, so I reserve listing for etsy to my commission slots, low cost customs, and other little things. I wouldn't bother listing anything on ebay that's not over twenty five dollars honestly, but that's just my opinion. they take a final value fee and a final shipping fee. Etsy takes a small fee of the final value fee but it seems consistantly much lower than ebay.
Also, when you start an etsy shop you have the ability to pay for 'impressions' or advertising, which pops up your chosen items a certain number of times per week when people search for something in that category. I'm getting a lot of business traffic from advertising [I only pay five a week , every other week but you can do up to twenty a week that provides a lot of advertising], but I also get a lot of traffic from google searches.