This is one of the reasons why I also don't like the new Hasbro soakers. However I'm going to stick to talking about design and not performance like mentioned.
I really hate their Nerf (N Strike whatever it is and such) styling on their blasters personally. It shows no sense of originality/uniqueness/creativeness compared to the older CPS and also air pressure soakers. A soaker to me always looks better when it has been designed to look good, but have simple lines to it, and the old Larami soaker designs did.
This is why I really liked the old Larami designs, they were simple, to the point and looked cool. Futuristic/space age but not overdoing the point. You could imagine them in their own little colourful hazy background world or planet. They didn't look blocky either like the new soakers from my point of view. The HydroBlitz to me is a great example of ugly and blocky. Even the Arctic Blast to me in terms of design isn't really my style of design, it looks like an iron to me.
I really liked the designs of soakers like the CPS 1500, CPS 2100, Monster (2001)/CPS 4100, Monster X and Splashzooka. Again, more fantasy style as while these looked a bit like some real guns, they just had something different about them that made their design look and fit nicely. The Splashzooka to me looks like a big, funky futuristic space style rocket launcher, I could go on but you get the point.
Also, for the colours I'm not really bothered about, I think the colours that have been used on older and newer soakers are good to me, there is a good blend of funky (CPS 2700, MI Flash Flood .etc) and sensible (CPS 1000, 1500, Monster (2001 .etc). There is a good balance. For how I play colours don't really matter (unless it is covered in pink

).
These are just my personal opinions, so don't go explaining to me that I'm wrong and that I need correcting.