Unlike in Standard BTS, the AI will shoot for Rifling. It's just that a certain neighbor still had crappy AI.

If you were playing this in vanilla, you'd be running into longbows near the end. Though it did take a while longer because K-mod seems to encourage earlier wars and it took me a while to get the techs I needed.
But that's an aspect I didn't really like. It's harder to tech and culture is nerfed. While the effects of culture are bigger, the raw culture needed for victories is harder, so peaceful ways of winning are less effective as Rep is a bit weak late game, plus the AI will crap on you if you don't hold up a military. In these cases I feel that getting quicker feudalism and getting machinery/engineering sooner than i normally would helps. I'm sure better players can achieve peaceful wins more easily, but it just seems like it's a lot harder to do.
On the other hand, vassalage is a really powerful civic, and serfdom isn't bad anymore. Also, State Property nerf means corporations are a bigger option these days.
Culture control is more important though, and cities further back can form a culture line, letting you flip enemy cities. Conquered cities are especially prone to flip now.
But yea, for whatever reason, K-mod is harder. You can still plow through individual AIs but there's always an AI near the end that gives you trouble. This is especially nasty on Continents maps, like this other Noble game I played where there was an AI that vassalized and conquered their entire continent as a 20 something city monster and then started to invade me. :S I even burned a third of his cities down, including his capital and a few nearby big cities yet he keeps on going. Does that even happen on Monarch on vanilla that often?
A few notes from this other game on continents:
War weariness sucked to say the least. I think I actually lost several rather large stacks and was like WTH where did it go?
I mean, this is normal speed and I lost 54 infantry, 55 tanks, 42 artillery, and 56 mobile artillery. And his casualties were worse, but that was thanks to nukes; he also shot a few at me but they didn't do too much.