This applies to UFC 3 too. No MMA game has felt like the fight could end at any time to be honest. A lot of that is because the hardcore gamers can't deal with a lucky haymaker giving them a loss to a scrub, which I understand lol but for it to feel like MMA, there needs to be an element of excitement that the fight could end at any time.
They need to make KO's from 1 or 2 well timed power strikes a legit threat, while also making it hard to do. The answer to that would be cardio playing a much bigger roll probably... you can throw fancy power techniques but if you don't finish, you're going to be exhausted late in the fight. Risk/reward.
I agree about hating the combo multiplier shit and I have my complaints about EA UFC 1 and 2, but I also think UFC 3 is not remembered realistically, particularly by a lot of people who gave up on trying to learn EA (not saying that applies to you). That game was very flawed itself. I probably put more hours into it then any game ever, I loved it, but it wasn't perfect and EA improved quite a few things IMO.