Well when i first started reading your post, i almost wanted to respond in a mad way. but not going to.
Like someone else said, the blasters a good size for smaller people, but im not small. im 200lbs and this little guy pulls me fine, that is, with all my mods. blasters may start off at the bottom of the food chain, but once done up nicely, there up there.
I think having a blaster is about how easy it is to mod and the parts available. your right, everyone that puts a bunch of money into them to go fast, should just buy something fast to start out, but what fun is that? and id never buy a shee. honestly, thats too much power for even me that loves to fly. a blasters like the middle class that you can make low upper class with parts but still keep it simple, reliable, moderatly low cost, but most important the fact you can modify them like crazy and non of them are the same. that goes for most quads, but id say, blasters can be easily modified so far different that its fun to have a very unique quad, performance wise and looks wise.
I was recently thinking about buying a yfz450 but honestly, i dont want one. ive put so much money and time into my blaster its to my preference and i love that. its more about the time then the money. i know ive modified her to be alot more powerful and handle alot better then a stock one. not the same buying a yfz450. its all done up to go pretty damn fast and handle nicely, but weres the fun in just riding fast.
maybe its just me, but i love to make my stuff different, to stand out from the rest. i dont like having something that everyone else has. doing it a different way.
hope that all made sence lol.