I won't comment much over the game aspects. Great post-apocalyptic lore a la Fallout, set in underground caves. Many cities, many factions, lots to explore. But I wouldn't recommend it to people who aren't very intimate and enjoy this style of game.
Even for those who like classic CRPGs, the game is held down by design decisions outside the actual gameplay, what is called "the metagame". It's designed so that your character is useless unless you spend 12 hours memorizing the wiki and planning things in Microsoft Excel. So beware. I enjoy hardcore difficult RPGs, what I don't enjoy is artificial difficulty from poor interface and build mechanics.
You shouldn't just follow a build guide like everyone recommends. The people writing guides already put hundreds of hours in the game, and are writing them for other veterans, not for you. So they often don't bother with silly things like "trap detection" and "constitution" because they memorized the location of every trap, know which battles are coming up, and know how to play glass cannons who never get hit.
This is a game where you can ruin an entire build because you put 5 points into a stat instead of 6. There is no respec.
My advice, unless you're willing to waste a hundred hours doing trial and error and reading the wiki/forums until you can make a successful meta build, is to empower yourself to do your own build in a normal game, using CheatEngine to grant yourself more skill points.
It won't change anything in practice, it doesn't matter that you have 80 points invested in a skill you don't use, or 0. All this does is give you breathing room and remove hours of planning from the requirements to win the game.
I realize this goes counter to how RPGs are usually played, especially as character planning and selling lot is usually a fun and addictive part of RPGs. But not in Underrail. Hopefully they greatly improve this for the sequel.