Some questions from a returning player!

Hey guys! It's been a while (few years!) but recently I decided to come back. Decided to boot up my main but I've got a few questions regarding the new elite specialisation traits. Just a bit of a background, I never really got around to doing any end game content back before I left (but I want to try!). Don't really have much money either. I've been reading a lot about the common meta builds around chronomancer and mirage. I currently have chronomancer fully unlocked and mirage 2/3 unlocked. I'm currently rolling a sword/shield + gs chronomancer, rocking a mix of berserker and assassins gear. Currently, I'm just trying to clear my main story line, map completion and do some world bosses atm. I definitely also want to try mirage once I have it fully unlocked but I read it's very very expensive. I also play with approx 300 ping so there are times when I find myself a little too fragile cause I was unable to react on time but it's been a lot better with this new build I'm running. My question as follows:

1) With the current state of the game, which one should I prioritise? Might stacking? increasing crit chance / dmg? % dmg increase? I ask this because sometimes when I look at builds on meta battle, they suggest traits like superiority complex but yet when I try it out, it doesn't seem to do as much damage than if I were to use imagined burden from the domination trait line (in fact I kill much faster with the domination line). Is it perhaps because I'm mostly just doing open PVE so I can't fully appreciate the superiority complex trait as everything dies too quickly?

2) Does a power staff build work? I saw this PvP build that is a lot like my current power PvE build (sword + shield / gs) and it seems like he's able to provide more utility through some staff skills. I was thinking of swapping over to staff to try but I also noticed that it is mostly based around condition.

3) I've also wanted to try a support chronomancer but as a solo player, is this a a bad idea? I usually don't play with anyone (cause I have no friends or guild lol).

4) Can I just do a cheap support chronomancer build even though I can't afford / craft ascended gear / provide 100% boon duration etc? I've always wanted to try an inspiration, chaos and chronomancer support that provides wells (with less than optimal gear) but I don't even think that's a good solo player build lol.

5) Can I play a mirage with only 2/3 traits unlocked? My last unlocked trait is mirage advance. I remembered having a very hard time trying out the chronomancer because I couldn't fully appreciate it until it is fully unlocked. Is it the same for the mirage?

Thanks for all the help guys!