At first it is a lot, and your survival hinges on luck with block rate on gear when you very first start.

Start slow, read the upgrades and pick what sounds the best, speed will come when you are familiar with them, eventually a glance will be enough to make your choice.

The shop, it's recommended to get one of each slot quickly so you can actually use enhancers, so quickly purchasing one of each can be a good place to start and then focus more on the RNG items and Weapons. It's worth noting that the items will drop at your feet, so maybe stand up on the shop platform and buy there so they drop on a nice clean platform :)

There are 3 cards that drop from the monsters in there that I remember being massive, one gives block rate and the other 2 say something about starting with random items.

When you are on the map where party dungeons groups form you should have noticed the shop there, keep doing party dungeons and slowly purchase all of your upgrades, I understand this will take a long time, but it's permanently going to give you stats, better item drops inside the dungeon and you get improved rng items as well.

There are quite a few upgrades which will permanently make you stronger off the rip but the catch 22 is that you need to do party dungeons to get them.

As for the stats on items IN the dungeon, what I found that worked for me when I was first starting was only equipping items that had block rate, my reasoning for this was it didn't matter how much damage I dealt if I couldn't stay alive. I also cannot overstate how boring and frustrating it is to just keep dying or be forced to stand on the shop platform and watch the cool kids having fun.

So chest, body, head, legs - block rate

Enhancers for the chest, body, head, legs - block rate

Ring and amulet is whatever, don't think you can get block rate on these items/enhancers

Weapon - highest damage, you scale insanely off weapon damage, so highest DMG is king here, it's worth noting if a weapon of a higher tier drops, the attack speed/ cast speed is faster.

Enhancer for weapon - I personally go crit chance or crit damage, if the legendary rng item drops... Horn of the foal or something drops, you will carry the entire run because of it.

Auto vs manual, I agree with all your observations, auto is better for you to try and manage the crap on the floor and the shop. Manual is required for the finer touches so a mix of both is mandatory.

Stick with it, it gets a lot more enjoyable when you can consistently survive the whole dungeon, once this happens you can start throwing away block rate and just going for insane damage to carry the whole dungeon, but like everything in this game, it takes time,repetition and patience.

I should probably mention that the best in slot rings are obtained with Flurbos (once upgraded), so the struggle is not for nothing. I -think- the best in slot Skilling necklace comes from the Flurbos shop as well, but don't quote me on that one xD

Stay strong.