Just won a big fight, and questioning difficulty

I know I'm late to the BG3 party. Been paying attention from afar since it dropped and got all the hype. Finally found myself without a game I'm invested in, and decided to download.

Ive played a little bit of casual DnD. And turn based jrpgs are my jam. So this is right up my alley.

First playthrough balanced, custom origin ranger, roleplaying chaotic good.

Going in blind. Ive managed to avoid story spoilers, and have no idea what 'builds' are good. No save scumming for failed dicerolls or dialogue checks. Trying to only reload if full party wipe, and reassess if I can realistically try the fight again, or if im just outmatched and should move along.

Fast forward a bit, tonight I accidentally stumble into the underdark at level 4, thinking I'm probably not ready for this, but gonna explore just a LITTLE bit to see how hard this area is... kinda expecting a tpk.

Suddenly, a Beholder (spectator), and it's resurrecting adds.

I managed to win the fight first try, though several of my party were downed often, I was able to save them several times, and finish the battle.

After the thrill of winning my most serious battle yet faded, I began to feel like... that dude should have kicked my ass. I made mistakes, didn't use my whole inventory, and still won.

I tend to play most of my games on hard, hardcore, or mod them for survival, and I'm beginning to feel like I may need to here as well.

I dont want to start over because so much has happened... but I also feel like I need to up it to tactician to be truly satisfied.

I also realize im probably still in early game, even if the underdark feels like it should be scary now... I dont want to up my difficulty, just to find out in act 3 I can't progress without spreadsheeting or going to the internet for 'optimal builds'... and so far there seems to be no way to 'grind' enemies or levels if i get stuck.

TLDR

Is balanced too easy, or does it ramp up later?

Is tactician going to require that I spreadsheet or go to the internet for builds?

Is there ever an area to 'grind' levels or gear?

Thanks in advance for keeping it spoiler free.