Level 69
Do your Bat Quest. Do your Dungeon quest. Do all your lv 68 and 69 quests. You should easily level and might even be 50% into 70 (I was ^^).

Level 70
Spam KKP and the KKP quest for this lvl. If you can manage, save the actual KQ quest. It wont hurt much if you turn it in, but it helps a bit later if you can manage to save it. Do some of your other quests if you wanna lvl a bit faster, but I still recommend saving most.

Level 71
You now have Crazy NavarRG 2, after doing part 1 for the licenses, part 2 calls for you to kill 60. This is insanely easy, especially with a party. When youre in Elderine, shout out and buy some Sand Hill scrolls. They are common, and cheap. Ride to the Navar spot in CP1, do the quest, and when done, hit a sand hill scroll. Use the port guy to go to Elderine. Much faster than riding back and forth. Save all your other quests.

Level 72
Still try to use KKP to your advantage. At lv 75~ or so KKP will only give you half a %, where now it still gives you 1~3%, depending on your party. Do a few quests, but clump them together again. Pick a map, and do all those. Continue til you level.

Level 73
Same as 72, but you might be getting fiesta gold bored of KKP now, huh? Well, Trumpy Remains, the lv 70 dungeon, is wonderful for exp if you can get a party. You can do the Dungeon quest now if you like, its best to do it in those big parties.

Level 74
This is possibly one of THE hardest levels. Expect to have to spam KKP and TR. Do all your quests, and try to hit 75 asap.

Level 75
Things get easier since you can use T4 scrolls, but not by much. Fighters will want to solo in TR. All other classes will want to party up. If you still have all those nifty EXP BOOST cards from apprenticeship and lv 20 (3 day exp), use them now and spam the crud out of TR.

Level 76
76 is just as hard as 74 and 75, but luckily, this is the last hard level for a while. Do all your quests, maybe kkp if you get fiesta gold bored, but stick to TR. Its your best bet through this level.

Level 77
Horray! You made it to repeat-quest-central.
You have two repeats. Uruga's young ladies missing 2 - Defeat 100 Black Incubus, and Monster Collector 2 - Collect 40 Lizard Knight Claws. Most people will do the Monster Collector because Incubus hit Mdef, and it can hurt quite a lot. So spam out Monster Collector. There is one quest you will actually want to do now, or youll miss out on its last part: Soldier of Destroy 3. Do this, and pick up the 4th part. Save the 4th part, and all other quests.