Not enjoying the combat, need some tips and advice

I'm trying to play The Witcher 3, but the combat is really hurting the fun factor for me. That said, I'm definitely a noob and perhaps I am just doing it wrong, so I'm hoping to get some tips on how to do it right.

Let me start with the positives: combat against lightly armed humans is overall pretty fun. I enjoy being rewarded for a well-timed parry with an opening to counterattack. I can see how that can make for a nice gameplay loop. However, it doesn't take much time playing the game to see that often times parrying doesn't work.

Even very early in the game, many attacks cannot be parried. The game does not make it clear what attacks can't be parried from what I can tell, but you quickly find out the hard way. Instead of being rewarded for your perfect parry, you are staggered and left open for attack. With my limited gameplay experience, it seems most monster attacks and attacks from humans with larger weapons cannot be parried. So basically, the most fun combat feature for me also seems like the least useful.

Instead, it seems like the optimal combat strategy is to time dodges (although often you can get away with spamming dodge vs. timing it), wait for the attacker to miss an attack, then counter with two or three light attacks. Rinse and repeat, maybe cast a sign every now and then.

This holds true from what I can tell in the first boss fight against the griffin. I didn't bothering trying to block, parry, or roll. Instead, I just dodge, get one or two light attacks in, and then go back to dodging. I was able to beat the griffin on my first attempt doing this, but it definitely did not feel very satisfying.

I'm really enjoying the story and writing, but I don't know if I can handle a ~50+ hour playthrough of dodge/light attack on repeat. Honestly, it would be a relief to hear that I'm just a noob who doesn't understand combat or that combat gets better as the game goes on.

Am I doing combat "right", or am I missing some fundamentals? Does the combat improve throughout the game?