the Baron
I understand that you're looking for answers relatively quickly, too, but take some time to browse the forum, because there are threads on every one of your questions. You'll find some valuable info in them.
Everyone of your questions have several answers. I'm sorry I can't give you one solid answer on one because each answer varies depending what subject you're building, what era, how much use it's seen, the type of paint you're using, type of thinner etc., etc.
I will tell you that Tamiya Extra Thin, thin and thick Bob Smith CA's, Testers canopy glue are the glues I use. I've never tried AK washes but use oils exclusivley with the occasional Tamiya panel line accent color.
The 105 is a solid AB with years of trouble free service. Replace the needle and nozzel on occasion and you're good to go. the pressure...it depends on what your painting, the paint and the effect.
Pigments can be problematic on planes if you don't do them right. They're better on armor IMO.
Highlighting panel lines, now that's a subject that's been knocked around back a forth. Again, personal prefrence and subject matter. Airline, no, warplane sometimes, tank, always, ship, depends on the scale. I will tell you that in my opinion, accenting the panels on a plane somehow make it look less toyish and more realistic. I don't know why, but it just does IMO.
I recomend trying oils thinned with Terpenoid. Beautiful results and easly removed if you don't like it. I use them for panel lines (along with my airbrush), rust, washes, dot filtering, wood effects and on and on. You can even paint with them although I'm not nearly that good.
I recomend Plasmo. He's a young YouTube fellow that just has a gift. I have learned much from him and he shows all the media he uses.
https://www.youtube.com/user/idaemon