I actually thought the game was rather morally challenging. It had a lot of flaws, but the morally challenging parts made up for those, to me anyway. I don't think it's a matter of maturity in that case, but rather a matter of... "what is your sense of righteousness." I can imagine the game gets really boring if you have a very straight-forward view on the question at hand, whereas somebody who doesn't have a set in stone opinion about those things might find it a lot more amusing.
It think that it's one of the game's strongest points but at the same time, the weakest. It either really sucks you in, or brushes you off.
Apart from that..the exploding enemies and stuff, it's a little 'childish' but I don't think you should let the visuals entirely ruin the experience for yourself. They're ridiculous, yes, but the moral dilemma in the game CAN be interesting, given it is at all appealing to you. I just think that, as I stated before, it's a bit of a shame to write the game off based on visuals (and I am well aware that is not the only reason, this is only directed at the possible group of people who did this) while the moral dilemma is really quite interesting.
I wish it had been exploited a little more, however, or had been introduced earlier.