What's your favourite gen, and why?

Hi /m/armoredcore!

As with a lot of people, I've recently got into Armored Core after all the hype surrounding 6.
I've played Gen1 to completion so far (actually preferred Project Phantasma to Master of Arena, contrary to what seems to be the main opinion) and am a few hours into AC2.
I consistently hear that Gen3 is the height of the series for many, so excited to get into that.

So far, I'm not loving the heat mechanics in 2, but I might still be adjusting. Found it interesting (and in some cases, frustrating) that being hit by weapons can increase your heat. Not looked too much into the meta builds for 2 yet, but overheating seems pretty unavoidable. I hear this gets better in 3, and is barely a thing in Gen4.

But yeah, what's your favourite gen and why?