If you're stuck between servers, you can always start a character on both and see which time-zones suit your liking.
As far as I know there are English clans in each realm on Ra, so you should be ok if you choose to play there.
Horus is pretty dead at late night on weekdays (~1am ish) or at least when I'm on at those times. Save for night invasions of course ^^. On weekends though the war is plenty.
If you want to join the Underdog realm, Horus Alsius is your choice, bud.
Welcome to Regnum, enjoy your stay ^^
If you want more info you can check out the wiki at
http://regnum.wikia.com/wiki/Regnum_Online_Wiki.
Regards,
Back-Slash
(psst, join Horus Alsius.
)