72v -vs- 48v efficiency with Navitas AC drive in Club Car Onward

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I just recently switched out the stock motor / controller in my Club Car Onward (2018, factory lifted, 23" tires) to a Navitas 5KW AC drive system.

Performance is decent - 30 ish top end, better than stock acceleration (but not by a whole lot).

I have the stock 48v 6x8V PD Plus Club Car batteries (US Battery I think).

At WOT on a just-off-the-charger battery, voltage drops to 44.5V on level pavement. Drops to 42.5 under hard acceleration. Batteries are in good shape, 6 months old and doing what they should - motor draws a lot of current (I have #2 wires on cart, but didn't make any difference from the stock #4).

I believe that this 5KW AC system was designed more for applications that are more extreme than mine - lithium and / or higher voltage.

Anyway, in looking at the stock 72v EZGO AC cart, which uses 6x 12v FLA, this cart appears to be popular because of good range (and power potential with aftermarket or modified controller).

I use my cart for neighborhood transportation, and am not racing other carts, so I'm not interested in killing the range or making the cart scary, but would like to find a sweet spot of solid performance that makes the cart fun to drive without giving up too much range for practicality. I realize the faster you go the worse the range all things being equal, but for short bursts here and there it's nice to have the power when you don't need to go 20 miles on a charge.

So I wonder if using around 440LBS of batteries that make 72v would be more efficient than using around 400LBS of batteries that make 48v?

Obviously EZGO thought so, but their motor / controller was designed for it.

My Navitas is good to 72v, so that isn't a problem

Higher voltage generally means lower amp-draw also, so possibly the voltage sag would be less on the 72v system, and some less capable LiOn packs may work also with 63-72v due to less amp draw while still delivering improved performance.

I'm sure somebody knows how 72v FLA compares with 48v FLA (same number of batteries) using this Navitas AC setup.

Thanks for any insight on the subject.