Cruisers, as a general rule, only have 5 or sometimes only 4 gears. You'll get used to it.
The VS800 has a high RPM motor, and will cruise all day at 85-90 MPH, so a 6th gear was not considered to be needed when the bike was designed. Adding it now would require a wider case, which would mean redesigning the whole motor, and then modifying the frame to accomodate it...too much effort for a 20 year old design. There is nothing wrong with a cruiser that tops out at 110 MPH- you don;t need to go faster than that anyway!
But I have owned 12 different bikes, with 4, 5, and 6 speed transmissions, and on every single one I thought "man, if this thing just had one more gear for high-speed cruising..."
I ride a lot of highway miles, so I changed out the rear drive unit on one of my 800s to one from a European-spec VX800 (a naked sport bike with the same engine, manufactured in the early 1990s), which is geared about 6% higher. I also swapped on a taller 140/90/15 tire, so between these two mods I dropped the RPM by about 10% at 65 MPH. But of course, that one is no longer as quick off the line as my other one, nor will it stand up on one wheel as well as the other one.
It was not a lot of work, but it did take quite an effort to track down a low-miles, European spec VX800 drive unit.