Hi devio! glad to have u playing

You came at the best alpha as well, the game is rly fun right now. I don't know your skill level so I don't want to assume anything but I find that, for starting out...
1: Play on the default difficulty then pump it up as you level/aquire weapons/gear, if ur having trouble with the early game. Mind you this is very dependent on skill lvl so I don't want to assume you are a bob when you might be new but amazing at games

Feel it out, start at adventurer, then turn it up.
2: I don't use any xp booster, I wouldn't recommend it as the zombies get harder in general and on horde night based on your level/game stage. You can check out your gamestage through tab and go check out your stats. I like vanilla settings for all this but its up to you.
3: Now this is one thing I would highly recommend if you are new, is you set the night speed to walk/jog instead of run.... at least at the start of the game. Unless you are good at dodging the zombies, you will spend your first couple of nights cooked up in a room trying not to get deleted by the ferals. I will say tho, I didn't rly start getting better at dealing with runners until I experienced them constantly but prob not the easiest thing to handle if you are new/early game.
4: I use default. It is up to you tho, if u want to add more block dmg I wouldn't go above 200 unless you really really hate farming or any grind. Dont raise AI Block dmg unless you are comfortable, dw they do plenty of dmg to ur base

I wouldn't reduce it either, it adds a really nice challenge.
5: I am still looking for better mods

There are tons out there, from maps, to complete game redesigns like Ravenhearst, I guess it depends exactly what you are looking for
Overall, my recommendation would be to try out the vanilla settings and if you are having trouble at night then reduce their speed at night. That should be more than adequate to give you a good game experience while also helping you out since you are new. Remember to add plenty of support to your base, if they knock out pillars, it should still stand. 4+ high on ur base should hold you over at the start of the game just fine. Gl