How far will the speakers be from your ears? How are you mounting them, and will the back of the speakers be mounted right up against the wall- if so, rule out the HB-1s, they have rear ports which shouldn't be blocked off. You will want to give those ports a couple inches of room.
You definitely won't want to use tower speakers from behind, you would regret that for sure.
I have both the HB-1 and Primus p162 as luck would have it. I haven't heard the Rti 3, but i have listened to the Rti 8s a bit. I have used the HBs with the HK3490 too, good receiver! The Primus and Hsu speakers are good, the Polk Rti isn't too bad either but I don't like how they sound at louder volumes. The Hsu speakers have the strongest bass, but since you already have a good sub picked out for them that isn't a concern. I think the Hsu speakers are a bit more laid back than the Primus speakers, and I think the Primus has more detailed highs. In my opinion the Hsus have more realistic mids, but a narrower soundstage. The Primus feel more open, but they don't handle loud volumes as well, but since you are not going to be far from the speakers, that wouldn't really be a consideration. I think because the Hsu speakers don't have as pronounced highs that I can listen to them louder for longer periods without hearing fatigue, but I don't think they are quite as neutral in sound as the Primus speakers. Both are good speakers, in my opinion.
The desk won't cause that much of a problem, especially since the speakers won't be right on top of it.