Definitely. You should always use a new set of gaskets when you pull the top end. I've seen friends try to get away with out it only to blow the motor during break-in. Not to say that nobody has ever gotten away with re-using gaskets, but the vast majority of the time that you try to cheat on gaskets, you'll get burnt. for the price of gaskets, just get nice new ones!!
Anything is an improvement over the stock reeds! Even just removing the stock reed limiters (but you'll need a reed backing strip if you do) can make a difference. 30 bux or so can get you some boyesen reeds, there are a few different styles, and they replace the stockers and you ditch the limiters and they definitely make a noticeble increase in throttle response. Lots of people rant about how much of an increase the Vforce3 reed cage with special reeds gives.....I don't have those though. I have gone from stock to boyesen on two blasters and noticed a very good bang for buck increase in throttle response.