I’ve owned both. I still have the BS2. I would say that if you are looking for something “warmer” than the A4, the Pulse 2 is not a good option. As RoyShade said: clinical. I would agree with that; even using the built-in drives it comes across as… overly precise. It’s got all this versatility, and if you said: I’m looking for something to do sound design with, it would be incredibly high on my list, but it definitely did not feel warm to me.
Wiring: you could send clock to either the BS2 or the P2, but you couldn’t sequence them from it. That might be one advantage to the Minitaur (which I also formerly owned; I preferred the BS2 to it… IMHO the BS2 suffers a bit from getting to the analog monosynth game early and its plastic case, I really think it’s an incredible synth, and it has, again, as RoyShade mentioned, a fantastic keyboard).
If sequencing from the A4 is a must, you’re really looking for CV interfaces: modular/semi-modular of all sorts (in the “complete voice” range: ToneStar, 0-Coast, MS-20, Mother-32, Pittsburgh Modular’s thing that I can’t remember the name of, etc…) or Minitaur, Arturia’s Micro/Minibrutes, Doepfer Dark Energy, the Boomstar line. The A4 does not sequence MIDI, which is what the BS2 and P2 use for external control. (BS2 has a built-in sequencer, but it’s fairly limited.) There are a lot of options on the CV front without going full-scale into modular and most of them tend toward “warmer” sounds, overall.