For the sake of realistic expectations, you should expect some forms of grief you dole out in the game to follow you onto the forums. Sportsmanship means something kinda funky and convoluted here, but a substantial portion of the forumgoers cares about the sportsmanship standards. As far as the forum -> game barrier, if you come across as dumb on the forums, you're more likely to get passed over for positions of responsibility in the game. No one wants bad leadership. (Don't worry, new does not mean dumb - we were all there.)

Aaaanyways...don't plan for serious combat training until you have a sense of what you want to do. Achaean combat isn't going to prepare you for Lusternian combat. The similarities pretty much end at "they're both built on Rapture." Play with group combat, play with guild/org work, play with our creative outlets, then plan. Even Blacktalon can bash, and that's all you really "need."

I think you could do fairly well in group and solo combat as a low lesson Celestine. Absolve truly is worthless in 1v1 and in groups I see far more people go down to judge than absolve (not counting people with beasts. Nerf beastmastery)

You could also do quite well without bothering to train Celestialism at all. Your setups will be based on the inqui chan, and in this your angel is mostly used to stop people from running. If you want to chance it and hope that web/carcer will be enough to stop someone, no Celestialism needed at all. If you need a little help, learn Blessed/Cherub and just use one invest (paralysis or prone/stun).

A Celestine should get plenty of kills with

Tarot/Astrology -> Trans
Sacraments -> Trans
Cosmic-> Master
Discipline -> wherever power regen is eough for inquisition

Monk is still better for low lessons though. Trans kata + spec (or not even trans if you're Shofangi/Nekotai) and you're good to go!

Just choose a guild you like! If you like a guild well enough every credit you spend on it will be worth it! I was an SS Bard who thought life was good. One day, I decided to randomly switch to MDs(Wiccans) and had to suffer a major lesson loss, and I've already received all the lesson bonuses for converting credits to lessons, but since I enjoyed being a wiccan and thought it was worth the lesson loss, I did my best to get guild-trans again, and after that I aimed for the skills that will help me at least survive skirmishes during domoths/raids. The choice is really up to you.

That's true, but I think it's tough to really get a feel for a guild in only two or three weeks, especially for new players.

I like the Harbingers well enough (though as a guild it's rather on the quiet side), but I don't even know how bards actually work yet... for hunting, Minor Second and a scant few other abilities are all I've really needed up to 50th circle. I won't know how it "feels" to use a bard until I start fighting other players, and that's quite a ways off. More than that, I don't know how other guilds compare to the Harbingers.

It's a gamble, really. You pick a city or commune, choose a guild, and hope for the best! If you enjoy the commune/city and your guild, you win; if you don't enjoy them, I suppose you move on to whatever else you think you'll enjoy. That's another gamble, and besides costing you lessons, will no doubt burn bridges with the people you're leaving.