It IS a bit disappointing to pay for a game with RMXP-style graphics, since so many other games are offering the same, but in the end it's just ONE aspect. If I bought a game, I'd think RMXP-style graphics would be a downer but 5 minutes into the game if I like the experience, I'll completely forget about it. It's just my opinion, though. After all, if you're selling your game to people who've never heard of RMXP, they are still new and fresh
One more thing. Even if the graphics are RMXP-style, custom graphics will make the game better any day. I say the less you use from the RTP, the better.
Speaking of which, using the graphics from the RTP for commercial games made with tools other than RMXP/VX is not allowed by Enterbrain, but I think you already know that. So if you can gather a comprehensive set of graphics from other artists and they give you consent to use them in a commercial game, I say it's all good.
One more thing. Even if the graphics are RMXP-style, custom graphics will make the game better any day. I say the less you use from the RTP, the better.
Speaking of which, using the graphics from the RTP for commercial games made with tools other than RMXP/VX is not allowed by Enterbrain, but I think you already know that. So if you can gather a comprehensive set of graphics from other artists and they give you consent to use them in a commercial game, I say it's all good.