16 tooth front is the cheapest option, 15 might need to remove a chain link (watch/plan carefully before cutting, can end up to short
, difference in link and pin counting etc.)
To short gear like (probably) 14 interferes with smooth handling of gears, somehow you notice it is "wrong" when driving.
The rotation of the wheel is then out of whack (range?) with the gearbox, shifting up is then ok but down is noticeable hard on the transmission.
It is a very nice cheap way to have fun "tuning" but then especially with short gear you must learn to drive properly again, maybe a roundabout is now in gear 2 and not 3, even 1 in hairpin, maybe locking up rear wheel (or activate clutch slip, how do you call that)
Both ways of range testing are nice, the short gear or the super 1 long gear when 5 and 6 barely can handle to push away more air. I like this setup in mountains, you can trash to rev limiter in 1 and barely shift because the range is so long.
Downside is passing neutral so many times is not recommended I think. Normally 1 is for driving away from stop, while driving you barely use it.
But I don't think front bigger than 18 exist, then you adjust rear but not so small that chain starts eating the swing arm.
For my EF with GSX-R engine I had this "blind" rear pizza sprocket made in 1990:
1984 Suzuki GSX 1100 EF replaced engine 1135 cm³ with 1990 GSX-R 1127 cm³