For desktop, VKB Gunfighter IMO - I haven't tried the smaller base AckAck mentioned, I don't find the stock base footprint all that much larger than the CH base, plus most of it is very, very thin and flat. Nice option though, Virpil does have a universal small footprint plate too that works on the Warbrd (and the T50, but you can't really use it on a desktop as it's almost a 1/2 foot too high).
The Virpil Warbrd is an option too, IF you have a TM stick you can use the Warthog handle on it, and that IMO is a really great option too, as the stock springs in that base + the weight of the metal TM stick = a very "CH like" feel in terms of moving the stick around (a bit more firm, not much, and a more precise movement back to center). There is another desktop option now for a handle/grip (Alpha), as the T50, Delta, etc are all way too high on a Warbrd on desktop IMO, and the WW2/F5 stick is limited in hats/buttons.
You can use TM grips on the VKB GF too, but you need an adapter (really hard to find for a long time - 2 years- but they've been in stock lately). The stock grip is great with the VKB though, so IMO there really isn't much need to get something else unless you want options for other types of planes/space or whatever. The connector VKB uses IMO is 10x better than the TM style used by Virpil too, but I know why Virpil went that route, just for commonality and simplicity.
Cost wise is pretty similar, the only handle/grip from Virpil that works well as a desktop handle (due to height mainly) is the new Alpha on the Warbrd, and that setup is $15 USD more than the VKB GF3 with its stock handle/grip.
Also, regarding VKB pedals, if you can live without brakes, they are IMO the most accurate of all the custom pedals out now (I have 3 sets of Slaw, MFG Xwinds, Ace2 Virpil, and the VKB pedals (earlier gen than what's out now, but close enough). You move the VKB pedals from your ankle more than from your leg/knee/hip, which is a more small motor skill motion, and gives a bit more precision (obviously personal pref). They are the least expensive as well, smaller footprint too (compared to Virpil's new peds, which are roughly the same footprint as the Xwinds and Slaws).
VKB GF2 on my desktop with stock base (putting this one up for sale once I get another GF3 in to replace it as I won't need 2 GF2 then).