I really like Parappa. I Try to play as all of the characters, but I always end up leaning towards him or fat princess.
I can usually pull off at least two Lvl 2 Supers, and If I get a good spot, another Lvl 1.
In FFA Parappa's Lvl2 is REALLY good, as I can usually get 3 kills (4 If I get lucky). So getting 6 or 7 Kills isn't too bad.
I love playing as PaRappa, and now that I've had time to fool around with all 6 characters in the beta, I'm leaning on him being my main over Sly (the other character I'm best with). Both have their strengths, but I like PaRappa's moveset a little more, and I find it easier to string together combos with him. I like his supers, though I've only used his Lv. 3 once (I get the same amount of kills with a Lv. 2, so why bother?). I've also gone on record before in saying that his AP-generating boombox is one of the more interesting and innovative moves I've seen from the roster so far.
I rarely see anyone else playing as PaRappa, though. It's mainly Kratos, Radec, and Sly.
Parappa is my main. I don't use his level three though. I use his level two and level one, but I'm sure his level three will be his best attack to use on the big stages.
I also use Radec and Kratos. Sly is good, but I don't use him much, never used Fat Princess, and while Sweet Tooth is my favorite character on the current playables, I don't like the character on this game because he's so underpowered.
I have mostly played with only Sly till today, today I used the other characters, Parappa can be very great when someone uses him to the max, had one match where it was only me using Parappa and someone else with Kratos (The other 2 got disconnected somehow), ended up going to overtime, just level 3 very quickly because of the added AP you get in overtime and used his level 3, so he's becoming a favorite of mine as of late
When you time his lvl 1 just right it feels **bleep** satisfying. I caught Sly's and FP's lvl2 with him a few times. And once you get into the groove, he can lay down the pressure.