Infeld Jazz flats on my L5000 and L2500 (as well as several non G&L basses) and love them. Low tension and no issues going through body on the L2500. I think I even used the 34" set. They also make 36".
yeah, I'm conflicted on the TIs..love them on my Alembic 4 string, but not so much on my main player (short scale Serek). I'm really curious how TIs sound on a 5er though...
During set-up, select each pickup individually, then press each string on the last fret and listen for "chorusing", lowering that pickup (if string action is set) until the chorusing just goes away. That's the maximum pickup height you can use. Anything lower is OK, with some loss of signal strength and some change in tone as the pickup goes down.