Also understand that with a slower roll, you have less invincibility frames, so avoid playing with the slow rolls for now.
Good to know, thanks. I didn't realise roll caused invincibility. Isn't that kind of stupid? Because then it doesn't matter if you actually manage to dodge the attack, you'll just take zero damage either way due to invincibility. But yeah, that certainly explains how boss fights could be about skill with no luck involved.
Regarding the rest...
I'm not really looking for spoilers relating to where I can find what.
I'll have to read about the summoning mechanic.
I totally slaughtered Taurus after applying lightning resin to my weapon. Probably a waste of the resin. Oh well.
You're right, the game gets interesting again once you start progressing, although I'm not a fan of the regularity of tough foes that I'm encountering now (steel bull, full plate mail knight with a tower shield).
But again, not looking for spoilers.
The only time i've grinded in this game is to get materials. And i never gave up on a boss though i came close to it twice, once with Bud Spencer and Terence Hill in Anor Londo and the other with the Four Faggots, but i got gud and succeed eventually.
Did you ever save (quit) just before a boss fight, then backup your save and load it if you failed? Because I used to not do that and it gets pretty ridiculous wading through the same area and same monsters to get to the boss just to study his moves.
The bosses are one of the highlights of the game.
Bosses can motivate grinding and looking for bonus areas, but so can optional bosses. I don't really see a reason to force them on people who don't like that sort of thing. If lightning resins were more common, the bosses would be practically skippable the way they are in Gothic 2 due to the availability of summon demon and fire rain scrolls. But instead of giving opportunitites to slaughter them easily (spoiling them for those who like a challenge), why not just make them literally skippable? It's not really necessary to impose your preferences on others when optionality is easy to implement.