Would a 7.3:1 or a 6.3:1 be best for crankbaits on a 7'1" Mod and spinnerbaits, swim jigs and small swimbaits on a 7'1" MH Fast? I have a Smoke and Arachnid in both gear ratios. looking at a Daiwa Zillion and trying to decide which ratio to get. Will be using 15 pound seaguar invisx. Thanks

You'd probably be fine with either. I fish all of those on a 7 speed. Now for cranks I would like a slower reel but I don't use them enough to get a dedicated reel for them. Also consider the IPT of the reel. My 8.1:1 I use for jigs and T-rigs probably has a lower IPT than the 7.1:1 I use for swimjigs and spinner baits because the 7 speel reel has a larger spool. 

I know some guys that swear by super high speed reels even for deep cranks, where traditionally you would use a 5.3:1 "winch" type reel. I'm not proficient with cranks except when trolling with the outboard (2.5 mph) but the good crankbait guys that I know say to burn them unless water temps are below 44-45

I'd go with the 6.3 for cranks and 7.3 for spinner baits, swim jigs and swim baits.