The DA35/2.4 is affordable enough that you could probably consider all 3.
But I think Focal Length is the main issue you're raising here. There are different styles of street shooting, so there's no one answer. But it's worth noting that most of the fixed-focal length cameras being released today have a 35mm equivalent FL of around 35mm. For example, the APS-C Fuji X100 matches this description exactly, with its 23mm lens, and the APS-C Sigma models (DP1 Merrill and DP2 Merrill) are near this with 19mm and 30mm lenses, respectively.
So it sounds like they'd both fit, though the DA21 might be an especially interesting option here. FWIW, I have an FA20 and FA28, which could both work here. But despite this, I just purchased an FA*24 because I miss having that focal length. As an f/2 FF lens it may be a bit large for street shooting, but it will be nice to have the FL back - this time with both AF and speed (unlike the otherwise nice A24/2.8 I had).
You may also like this lens:
Sigma 24mm f/2.8 AF Super Wide II Lens Reviews - Sigma Lenses - Pentax Lens Review Database
I've had both an MF and AF version. Many people like it, but I found the IQ lacking, especially wider than f/4 (although admittedly, this problem was compounded by the fact that it tends to overexpose by a stop or more). And the AF may not be as fast and accurate as you desire. But if they're still going for around $200 it might be worth considering.