speaking as a fellow lefty islander...
I use all track, but if I were to mix i would use:
Heavy/fresh: Ebonite mission
Med/middle of block: track 505t (more versitle than you think, will fill a large hole in the bag depending on drilling and surface)
Late game/dry: Track 505a (could get away with 300c or trop heat pearl or similar but since we rarely see bone dry on the left you don't want to get too weak. Possible a 300c with 3-4k abralon for control.
I use (depending on the house):
hvy: 715T/505T
med: 505T/607A
dry: 607A/505A
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