Been going through something similar, trying to replace my DA35/2.8 Ltd. with something faster.
35mm was okay 'normal' focal length, but all else equal would prefer a bit wider.
My list included yours and these others:
4) Sigma 28mm F1.8 EX DG ASPHERICAL MACRO ~USD379 new
pros - 'most' normal focal-length (28mm = diagonal of APS-C sensor), good IQ, nice bokeh (9 blades), very close focus (1:3), not expensive
cons - very bulky and heavy, Stigma
samples:
Zenfolio | Sinan Tarlan | Sigma EX 28mm f/1.8 Full Size Samples
5) Voigtländer Ultron 40mm f/2 SLII - ~USD379 new
pro - typical Voigtländer IQ and construction, tiny-but-not-too-tiny, cool close-up (1:4) lens attachment, 9-blade diaphragm, price
cons - a bit long for normal lens, no AF
samples:
Voigtländer Ultron 40/2.0 vs Pentax FA 35/2.0
6) SMC PENTAX-FA* 1:2 24mm IF & AL ~USD500 used
pro - genuine SMC, AF, high acutance
cons - not available new, a bit pricey, mixed reviews about bokeh and corner sharpness, not really small
I narrowed my list down to (4) and (5) but in the end I found a relatively inexpensive used Sigma 28mm f1.8 II Aspherical (MF), a much smaller predecessor of (4).
But out of all those lenses, you can't really go wrong with any of them. You/we are spoiled for choices, it's a good problem to have.