Work on perfecting the gameplay, but I don't think you should rush a game out with bad graphics just because the rest of the game is finished. Spend a bit of extra time refining your art, get some advice from the pixelart forums PixelJoint and Pixelation and release a game with both good gameplay and good graphics. I don't see any reason why the game would need to be rushed out before the graphics looked decent, there are no deadlines anymore. I don't expect Henk Nieborg-style masterpieces, but try and put a little bit of effort in, or just ask around for a graphic artist to help out.
People don't want to seem superficial so they'll always claim gameplay is the only important part of a game, while saying that looks/graphics mean nothing to them at all. But at the end of the day attractive or stylish graphics make a game more memorable, and you'll capture a lot more attention with the screenshots.
Although a few people here have replied here, I wonder how many will actually get around to playing your game when you release it. I think sometimes people just like to post for the sake of moral support, but don't actually go out of their way to try new Amiga software. How many of them downloaded, played and commented on the recent "Fallout 3" fangame that was released here on Amiga.org, for example?
Make the best game you can, don't compromise. Unless you've come up with some revolutionary new gameplay idea which hasn't been done, chances are your game will play pretty similar to a heap of other games already out there in whichever genre you choose to program the game for, so things like graphics and sound will really be the only thing to set it apart from the rest.
Just remember that we're here to help if you need it, and there's no harm in teaming up with someone to get the job done better or faster.
Remember this: Nice graphics draw people in, good gameplay keeps them playing. You need to bait your line with something or you won't get many bites.
