Apart form Trainz the only other thing I really liked was Command & Conquer not any of the first person shooters but the strategy based ones. All of the old ones, especially Tiberium Sun, wouldn't run properly on later machines. When I went apple and installed the Parallels VM I considered installing he windoze games so that I could play them again. I have VM setup for windoze to test IE8/10 for Channelpace.
But a game called ‘Company of Heroes' which has been around for a while was ported to Mac with all three editions available, it was available on the Apple store but the download of 12gigs over the satellite wasn't on, picked a DVD version up from eBay for less than $20 and I must say that the game is quite enjoyable, not too much overkill with the graphics, the music is not intrusive and the game play it very interesting .. translation I keep getting my forces killed. I tend to play one scenaro a day while pondering more coding specs for Channelpace.
If you are into C&C and have not looked at Company of Heros give it a go .. available for Windoze and Mac