Ok, first off, I like these types of games-second, I'm not that good at them most of the time, so I expect to die alot. So, playin this, I died ALOT, but the leveling up helps with that-a few times I had to power level just to make it past a stage, and even then it was tricky. The different weapon choices are pretty neat, and some are better for certain levels, which I like. Being able to adjust the angle of the weapons is absolutely a great option, and it really saved my bacon alot.
Now...as far as 'negative' parts, well...first off, the standard enemy bullets are not that easy to see, especially later in the game where there's stuff all over the place-that's not a huge deal, but it is kind of annoying and makes dodging them pretty hard. Second is the fact that we can only level up to 20, then it stops-that might be fine for some people, but I just can't beat the last level no matter what I do or how I configure my guns, so being able to power up more would be nice.
All in all, it's fun and well made, but there could be improvements-also, I think it would be neat to have a more customizable leveling up sequence. Get the base boosts, sure, but then be able to pick one of them to improve a bit more. Specific weapon leveling or enhancements would be a pretty cool idea also, or I think so, anyway, but maybe that's just not something you wanted for this game in particular.
When it all comes down to it, I like the game, but it's frustrating at the same time, which is, unfortunately, a trait that is far too common with these types of games. Challenge is fine, but I'm one of those people who, when I get too frustrated, I'll stop playing a game for a long time, so.....I don't know, maybe an adjustable difficulty would be a way around that. Certainly want to see another one like it, though!