Yep, the Turks in Early are absolutely one of the more challenging factions in vanilla MTW/VI. I don't play as them very often, but they're usually pretty tough when I do. Since you have no choice but to go to war with the Eggies and/or the Byz if you want to expand, it definitely makes for an interesting campaign.

(I've just never been that fond of them due to their large number of mounted missile units. I should probably just get over it, but some habits are hard to break. )