Well, the best solution is just to use a high quality CRT. If you must use an LCD, buy an RGB modded system and run it through an XRGB-mini. Think about what you want as far as mods go and try to get a system that already has it done. This will save some you some money.
If money is no object and you want to play original games, I would recommend getting a Turbo Duo modded for RGB and maybe a region mod to play PC Engine games.
The other extreme would be to buy a PC Engine Duo modded RGB, then buy an everdrive for card games and use CD-Rs for disc games.