The TonePort UX2
Looks like all its control functions are s/w based, so...no go on this one.
The Alesis IO2
Doubtful, given its powered via USB and includes no output options other than USB. I suppose theoretically you could hack the USB connector to run power from an external power source, and a digi-signal out to a non-USB source, but...maybe, maybe not.
Also, what's the verdict on the UA-25?
Nope. Its configurations, e.g. bit-depth, sample rate, etc., are all managed on the software side. Same issue as the UX2 above.
Are there any other new budget preamps out there, essentially replacing the niche that the UA-5 held?
None of which I'm aware.