I'm pretty sure the male Viera will be tall. They won't be as tall as Roegadyn or male Au Ra, or even male Elezen. But they'll definitely be taller than Midlanders and Miqo'te for sure.

In an interview the team said that they didn't want male Viera to be just "tall Miqo'te" (a tall version of the demirace that's currently in the game). That alone confirms that the male Viera will be on the taller side. Consider what Yoshi has said about designing male Viera to be similar to Elezen, as well as the numerous comparisons made from the trailer screenshots.

As for male Viera looking androgynous, I don't think they look androgynous at all.

They just look like your typical young anime protagonist with longer-than-average hair. Just because they're not hypermasculine doesn't mean they're not masculine at all.

They're slim but athletic with lean muscle. Not all males are naturally bulky. They might look less threatening or powerful compared to the bulkier Highlanders or Roegadyn, but that doesn't take away from their masculinity.

EDIT: On a side note, I think male Viera will be pretty popular (at least more popular than male Hrothgar). Despite the hair and hat limitations, I think they'll end up as third most popular male race after Miqo'te and Midlander. Roegadyn, Hrothgar, and Elezen won't provide a lot of competition, although Au Ra and Lalafell might go toe to toe with Viera. As for Midlanders and Miqo'te, I think there's just too many of them for Viera to outnumber. They'll pull from Miqo'te numbers, but they'll pull from all the other male races too. When female Viera first came out, the two female races most impacted were Roegadyn and Elezen, with Miqo'te and Lalafell losing very few of their numbers, so I wouldn't be surprised if something similar happened with male Viera.