For leveling, I used the paper for a bit, but started just doing it by eye pretty quick. This takes a lil practice, but doesnt take long to get a feel for it.
Basically, when you level everything is going to be up to temp so the fan will be running. You can feel/hear the vibrations when the nozzle touches the bed.
Maybe even better if the bed surface is reflective. You can lower the nozzle until it just kisses its reflection.
Level isnt something you should have to mess with very often though. Like just keep an eye on your 1st layer and maybe tweak it once a month or evey other month thing.
To do this you need good firm assembly, and 1st layer stuff pretty decent so you arent having to jackhammer stuff off the bed. Be as gentle as you can when pulling parts.
More often just a minor nozzle/bed gap tweak was needed to get dialed in. This was prob more of a one/every other week thing.
I always just used an adjustable z stop, but you should have a z offset you can tweak on the lcd with manual mesh leveling that does the same thing.
IMO, 50% speed is a good rule of thumb for 1st layer. You can go faster depending on setup, think Im 40mm/s PLA on blue tape right now.
I dont mess with any height settings here, just running the same as the rest.
.4 layer, .5 line width, .4 nozzle right now. This goes against the typical rule of thumb for nozzle/layer height, but its just a rule of thumb and you can get away with much more after you get a feel for things,
And for sure, 1st layer is absolutely critical.