Any way to find out sources of ways to get Crusader EXP efficiently? Having a tough time with the extremely limited amount gained from some activities...

Alban Knights Training, or doing "Raid" missions (or even Soloing) seems like a few ways, but Crusader EXP for the former is purposely gimped to require many many many playthroughs to get 1 level up...

If you're on the Nao server, Nossx3 hosts raids for girg dailies just about every day on channel 4 at 8:30 PM PST. Definitely getting the daily missions and weekly missions seems to be the best source of crusader EXP. The title "The New Divinity" will earn you 5% more exp and there's also the Ancient Alban Knights Robes will give you 10% extra exp.

The majority of the exp you're expected to get come from Apostle Raid quests, both the Weekly and the Daily. Baltane missions sometimes awards exp pots, and Alban training rewards a small amount of exp. But for both of those the Daily Quests would on average reward you more and you're probably able to get up to the Mid-Completion Bonus every day by combining Solo-able Girg. and Solo-able Hasi. requirements.