Increased load on starter?
An alternator has a thing called "cut in" RPM, meaning there is a RPM where the alternator STARTS to charge. The starter does not turn over the motor fast enough for the alternator to put much of a load on the starter.
A bigger battery has a higher capacity BUT it also has a higher internal resistance, making it harder to charge. A bigger battery requires a bigger alternator. No real gain there. A more efficient battery would be a good thing.
A belt or chain to drive the alternator can actually waste LESS energy than a rotor mounted solidly on the crankshaft. The crank speed changes in each rotation. The crank rotates faster on downstroke and upstroke than as it goes over TDC and BDC. A LOT. So the rotor has to speed up and slow down on every crank rotation, just a little bit BUT that little bit times RPM makes for a considerable force. The belt or chain introduces lash into the system, smoothing out those pulses, resulting in less parasitic loss.
... and in the case of the 'wing, you can remove the stock BIG honkin' permanent magnet rotor and install something MUCH smaller with the same or larger output with a lighter rotor with a smaller diameter. WIN WIN WIN! (In my case I used Denso that the whole alternator weighed less than the Honda rotor)(oh AND with the alternator mounted on the timing case I could work on the alternator without taking the motor out of the bike. On old wings you need to remove the motor, the BIG motor with shaft drive splines to line up, a ROYAL pain, to service the alternator and the clutch).
The biggest problem for rectifiers is heat, and the heat comes from resistance, and that heat makes for MORE resistance and so on and so on....
The 'poor boy" rectifier is terribly in-efficient because it uses zener diodes. A design straight out of the 1890s (Called a "bridge diode"
https://en.wikipedia.org/wiki/Diode_bridge). A modern mosfet rectifier is MUCH more efficient and cooler running.