By losing Mark Strong and Nicolas Cage from the original, Kick-Ass 2 had a huge hole in need of filling at both sides of the spectrum and despite Jim Carrey turning in a wildly impressive performance (in relation to his frustratingly short 8 minutes of screen time), it is perhaps on the side of evil you notice this more. Christopher Mintz-Plaisse is woefully under-served as the films main foe and despite having a few funny moments throughout, he is never given the chance to shine and the film's bizarre plotting ensures that for every one step forward (nick-naming seems to be a talent of his) he takes two steps back. Evidence to this is the one scene cameo of Iain Glen as his Uncle in prison who threatens him to stop pursuing Kick-Ass, to which Chris says no, forcing his Uncle to kill Chris's only confidante (in itself, a very effective scene), only for this to do nothing to dissuade Chris as he continues with his plan anyway. And we never hear from his Uncle again.
Unnecessary scenes like this plague the film throughout and they really hammer home how disappointingly short Carrey's role as Colonel Stars and Stripes is. His performance is compelling as he sinks into the role, but rather than revel in it, the film only allows him two stand-out scenes and then continually uses it's supporting cast of character to eulogise him and ram down the audiences throat just how important he was despite his brief tenure as the leader of the pack. You really wish they could have trimmed the fat in other sections of the film to afford more Carrey time as the crazed Colonel.
With the lack of the Colonel on screen, comes a lack of fight. The film falls into a lull after his character meets his demise, with the delicate escalation of events in the first film being replaced by a mish-mash of random events seemingly undoing each other as they reach their rather uninspired climax. Moretz is again eminently watchable as Hit-Girl, but considering the most she gets to do is make people defecate themselves and stare at her Father's suit, the viewer can be forgiven for missing Big Daddy as well.
The film itself is not a bad one, it can have it's rather enjoyable moments, but in comparison to the first one, it falls decidedly short on all levels.