I spend an inordinate amount of time breaking down and analyzing pay-out schedules and tournament structures. The O.P. asked "how it (a T50 chip) would fit in for antes?" Fantastic! IMO, the T25 is a nuisance chip when running a NLHE tournament that has antes. T50's are easier to race off and easier for players when it comes to posting their blinds. For some inexplicable reason, players need to to check the clock or be reminded as to how many green chips they need to post for an ante. Could be the simplicity of posting a single chip in the first few levels after the antes are introduced. (I really don't know why. I am only guessing. You have to try it.)
Maybe Seeking Alpha has something to say on the subject.
Also, I happen to like the colors traditionally used for higher denomination chips. I don't know what extra flexibility a T25 chip gives you when you can work your structure around to fit one or the other.
To note: I really don't see the necessity of having an ante for tournaments that have less than three tables. 2) A T25 chip for tournaments that don't use antes suits me fine.