Alright, I did what Flameberge suggested and I got from Lv52 to Lv64 using Alby Adv HM in 4 runs, 3 of them using combat exp 2x potion. I kinda feel like, even without the potion, I think I can hit 70 no problem. I think the curve gets ridiculous shortly after that, though. Also, food for thought, Laighlinnes can play r1 scores with playing instrument as low as rank 5 (Lv60). Though at least not without 5 fails before it happens.