uh, there are plenty of changes to this game.
Orb stacking change, new heroes, new unique abilities never seen in DoTA (Zephyr), courier abilities, reconnecting, stats, matchmaking, maps, new graphics for well known models, lots of balancing with items.
Also your argument (I would say QQing) about casters not scaling in any meaningful way is bullshit.
1) Casters are more powerful early compared to carries and are usually support.
2) Carries (usually agility heroes) are underpowered at the beginning of the game.
3) It is your playground as a caster early game. You do good there, you are likely going to win.
4) Like hell you don't scale well. Zeus from DotA scaled to do more damage as everyone else got more powerful. There are lots of examples.
5) Caters are usually support. It's like you're complaining that you choose a cleric to heal in a MMO and can't dps well now. That is what is great, after 1 game you can pick a new hero.
Full of crap again about not making a move. The ones who make move are the winners. A key gank one a hero. A tower push, an awesome ult pulled off to coordinate your team annihilating the other side.
I could go on and on about other points...
My guess is you're a n00b at the game still. Which is fine. The learning curve to this game hurts as much as Eve Online.