Fun little thing I've noticed today when I was fooling around with my low lvl miner out of boredom: resource nodes spawn ALWAYS at the same location each time you enter the map during one session. If you could find a rich spawn point just by the map exit you could harvest the nodes, exit the map & return and harvest them over & over again.
The best thing is: if one of those nodes is enhanced (i.e. has higher gathering rate) - it will be enhanced EVERY time.
I'm not 100% sure that every player has the same node grid setup when he enters the map, but in Central Thanlan the part just beside Western Thanlan exit worked wonders for me. I had two nodes (Rocky Outcrop) just by the exit line, on of them was enhanced. It took me about 30s to gather both, exit & return instead of chasing crazy respawn pattern. Lvl'd up 14-->15 in about ~12 minutes.
EDIT: I've logged in just now and found that my node setup has changed a bit. Relog/client restart sometimes changes it, but I'm still not 100% sure does it change every time - I'll update this post once I've found out more.