Nice Wellcraft. You can keep trying some different products, but I don't think you are going to get the results you are looking for. There comes a time when you have done as much as you can with the gel coat to bring it back and it seems like you are very close to that point. You can try using a polish with oils in it to temporarily improve the appearance, but thats the only suggestion I can give you on top of what you have already done. If your going to be keeping the boat for a while, look into getting the hull painted or re-gel coated.
Here is my old 23' Wellcraft Nova that I brought back from the dead with 3M Super Duty compound, followed by Finesse it II using wool pads. Never got it to the point where I was happy but it looked 1000% better than what I bought it.
