I finished the game yesterday. It was as great as I expected and, of course, I think it's too short… Anyway, I prefer quality over quantity, so I can see past that. I have a few spoiler-free things to say:
For my first run, I played on normal (as I usually do) and it was a bit too easy. I can count my deaths on my fingers and 3 of them were because I kept playing around with sharks and the rest mostly occurred due to me ignoring the enemies to admire the scenery… Knowing that I haven't played a R&C game for about 2 years, I think it's safe to say they definitely lowered the difficulty level for this one. So, I recommend playing on hard if you want a challenging game. Also, disabling the auto-aim is a must. Plus, I watched my younger brother play on easy and it's definitely simplified for kids. All of this is understandable, they wanted to please the fans and also appeal to a new, much younger audience.
I encountered my first bug in the game: This happened twice, first on Novalis and then on Batalia. Clank's voice got a weird echo effect and I swear it sounds exactly as if he is telepathically communicating with Ratchet, quite funny.
The wrench isn't as effective against enemies as before, therefore you rely more on weapons and ammo management is more important, I like that.
Best cheat in the game: bolt styles, but I also like the armor skins.
Worst cheats (inmo): infinite ammo and invincibility… Why would you do that? Who thought this was a good idea? Sure, you might have a bit of fun at first spamming ammo, but seriously these 2 completely ruin the game, so why would you use them? Why do they exist in the first place? 
I look forward to see more of the Nefarious in the movie, he's awesome.
Also, now I know that here in Europe we pronounce it "Combuster"
Don't open if you haven't played the game already:
The boss fight with Qwark was hilarious. When he used the Groovitron on Ratchet for the first time I broke out in laughter 