What is with this obsession of unlocking?
This isn't Battlefield afterall... thank god.
A game should be fun to play, from the first run onwards. Rewarding players who invest their life into playing a game just seems wrong. Either you're going to keep liking it, or you're not, changing the way a weapon fires doesn't make the game more fun, and adding weapons is pointless, especially in a game with no managed/official servers.