I'll play...
I actually do have my "emergency in case I obtain a FF camera" kit... and it's full of Tamron Adaptall-2's!
Even though I'm shooting only APS-C (K-3 II, K-S2, K-01) the following lenses impressed me due to good edge performance, which leads me to believe they will be decent on a FF sensor:
Tamron SP 17mm f/3.5 (51B/151B) - its sharpness is OK - not great - when stopped down a bit, but the corner-to-corner performance is consistent. Peak sharpness is kit-lens like, but the corners are better than the DA 16-45, Tamron 17-50/2.8, or even the DA 15 Ltd. The lens also can produce surprisingly rich color with medium contrast, which IMO provides an organic touch to the images. Generally available for under $200.
Tamron SP 24-48mm F/3.5-3.8 Model 13A - this lens is sharp edge-to-edge and is generally good throughout its range. Saturation and contrast are middling, and at the long end images are dull unless stopped down. Aberrations are well-controlled for an older lens. It really shines at 24mm. Generally available for under $200.
Tamron SP 35-80mm F/2.8-3.8 Model 01A - I think this is the sharpest zoom I've ever used. I've had 3 copies of the vaunted F 35-70 - and I still have two of 'em - and this lens is sharper. It's something of a cult classic. It's sharp everywhere, pleasing color and contrast, and has near-macro focus. Generally available for under $100.
Tamron SP 70-210mm F/3.5 Model 19AH - This lens is sharp all over, except for at 210mm f/3.5, and even then it's not bad. It's noticeably sharper than the F 70-210, the color and contrast are just as good (IMO) and is significantly sharper on the edges. It also has near-macro focus. Generally available for under $100.
Honorary mention -
Tamron Adaptall-2 24mm F/2.5 Model 01BB. The edges never get that sharp, but the center is good wide open. It's very nice for shooting
things. One downside is the out-of-focus rendering is not that good. Generally available for under $100.
All of these lenses are susceptible to flare, moreso than their SMC Pentax counterparts. But they are generally enjoyable to use and are fine lenses... if you get a good sample. That's one of the challenges when buying a legacy lens, we don't know if there has been abuse or things have perhaps drifted out of spec just from use.
Oh, for a long tele I'd recommend the
SMC Pentax-A 400mm F5.6 or
Tamron SP 400mm F/4.0 LD-IF Model 65B. The Pentax is my favorite lens ever, not overly large or heavy, a joy to handle and sharp. The one bugaboo is that CA can be a bit strong. I use it for birds and beasts and butterflies. The Tamron is faster, sharper and has less CA, but its also larger, heavier and doesn't handle as nicely... but it's a very fine lens.