G1 had the most appealing babies, IMO. Their proportions are perfect & they have such endearing faces, without looking forced. The poses are adorable too. Who could resist a little candy-coloured equine with their head raised curiously, or crouched ready to play?
G1 also wins for its Wingers (those delicate little butterfly wings & weather/flying critter designs are a match made in Heaven) & its variety of colours & poses.
It's difficult to imagine a grey mare being produced in any other generation.
The only thing I think G1 did worst was its plushies; they've always looked really odd to me.
Having grown up with G2, I adore it, but the over-abundance of pink always bothered me.
However, the later lines seemed to experiment more with bold colour schemes & quirky symbols. We ended up getting beauties like Copper Glow, Princess Crystal, Seabreeze, Water lily & Snowball, to name a few.
So G2 wins points for pushing the design boundaries. I also like their logo & plush range best. Those beanies are so precious.
Props for creating the first winged unicorns too, although personally I would have preferred to see molded wings, rather than clip-on.
I adore G3: the variety of poses, colours & designs were all spot-on.
There are some really striking colour combinations: Wishawhirl, Garden Glade, Citrus Sweetheart, Denim Blue & Applejack are some of the ponies that spring to mind.
Methinks G3 had the best boxart; Ponyville looks like such an idyllic, inviting place to live, & the character profiles for each pony are a really nice touch.
However, I've never been a fan of their baby ponies; they have such bizarre anatomy & look... stumpy.
G3.5... let's not go there.
I'm not a fan of the G4 toyline at all. The style just doesn't seem to translate very well from cartoon to 3D.
The range of non-show characters they produced in the early days was promising, but now they've resorted to churning out endless clones of the Mane Six with slightly different features each time.
I've also found most of their gimmicks to be trashy & ugly, particularly when they spatter the ponies with random decals. The complete lack of quality control is the most off-putting thing of all.
It also looks really lazy when they slap the same old vectors on every single piece of merchandise.
After that rant, I
will say that G4 Pegasus wings look the best out of all gens, IMO. They're actually very nicely molded, & I like the way they stand out from the body, making the species more unique.