A Carcano would be a good addition then, as they are definitely different (and in my opinion one of the best bolt action designs). Gain Twist rifling, simple bolt, mannlicher style charging system, light low recoil round (at least for the era), one of the better cleaning rod holding systems (threads into the front band instead of a block on the inside of the stock), and from the ones I have handled fairly accurate with good ammo (though good ammo can be hard to find).
Other ideas if your looking for different systems, are a Portuguese M1904/39, a Austrian M95 rifle (straight pull with mannlicher clips), any Swissrifle (K31, K11, G11, G1889 etc.). Oh and two other good ones not to forget are the French
M1907/15, or 1886 Lebel.