1) For solo just use survivability:
/ dnc or nin are ideal 30+ for solo. 50+ you can go for /war and use whm.

2) Dont bother trying to skill up and level at the same time, youll just die a lot. At 30 I went and got SS skill from 0 to capped for 25. Then repeated that again at 50 (capped for 45) since 5 levels over a mob is enough to let your pet tank it pretty reliably.

3) After 200 skill there are no short cuts, other then getting burts. The increased # of WS will increase your skill up chances. At 75 I had it capped at 68ish. Then i just went 75 to 90 and still only had lvl 75 skill. Got burts and its gone up to 85ish now.