It's not selfish when I do contribute for parts breaking to the hub's siege progress and heal team members too.
Also keep gathering tracks and gold chips to increase the pursuit level, when most players I see don't bother to do this as much.

Don't tell me you will keep joining level 1 pursuit siege to "help" when part cannot be broken easily here, when the hub's pursuit level is at 3 or 4 ?

Also, been reading some articles, but want to hear your thoughts; does negative affinity means no chance to crit, or does it mean your normal hits can actually hit for lower than normal/0% affinity?

I really wanna learn lazy ass weapons like lance. LOL just block and poke. 

So as long as it's negative value, just treat it as absolute number your probability of hitting lower damage; -30% means 30% of hitting only 0.75 or 75% of your base damage?

what's wrong with maining hunting horn?

why every room i join, even low rank ones would kick me when they saw my 'trumpet'

Unfortunately for you, that person must be stupid for kicking you.
I play a lot of HH, so far haven't experienced anything like that at all.
Misconception here. Yes, the ideal part is to deal damages while buffing, but there are self buffs that HH users need to do for themselves in order to deal the best damages for the main buffs later. Just because a HH user is standing aside buffing doesn't mean he/she is bad. They could be doing the self buff. Also self buffing is to ensure that they deal higher damages, attacks won't bounce, and run faster & etc for later. And for some monsters like ATK, you need to keep the buffs up all the time and there are no a lot of windows for you to play the song while dealing damages, thus standing aside to keep the buffs up for all the other players!

Those people who kick HH users just because they are standing aside to buff? At least they are buffing, I have seen plenty of other weapons who are just purely leeching. A good HH user is someone who knows which horns to bring for different situations to help and support the team the best, and able to keep up the buffs up! Dealing damages in a team is definitely a welcome bonus! But when you are a team, your buffs help players to push through, kill faster, and survive better!