You are probably right on the sizing Steven, depending on weight of line it
might be a bit tight getting a Switch line on the Nautilus and a wee bit of overkill with the space on the Abel.
That said you'd probably be best waiting to see what balances the rod you buy; I tend to look at Switch rods as small double handers and I'd suggest that you consider looking at a reel that's at the small end of the double hander reel size - so an Orvis Hydros V, an Abel Switch and so on. Abel Switch looks nice......
Plenty of choice out there though - go treat yourself
H