nothing in-game suggests that tyria's population feels strongly driven to reproduce, not even amongst the charr who are all about bolstering their military capacity. again, this doesn't even begin to apply to the sylvari because, from a reproductive standpoint, they're all (as far as we've been shown) neuter, while the norn are shown to engaged in their hedonism regardless of what's going on in the world around them - the battle against the elder dragons hasn't stopped them from throwing moots and getting outrageously drunk, and I really doubt it would stop them from having sex with whomsoever they please either.
at the risk of not really contributing much to the conversation, I'd argue that the sylvari are actually pansexual - "Sexually attracted or open to all people regardless of gender, gender identity, or sexual orientation." - as opposed to hetero/homo/bisexual, as I can't recall ever having seen sylvari actually discussing gender preference - because gender doesn't matter to them!
and it's a logical progression, considering they're unable to reproduce between themselves and sex, for them, is just for fun. they're not sexually super special snowflakes for the sake of it, or because anet wants to be inclusive and politically correct - it just makes sense given their circumstances.
I run a very similar build, but I take 20 in air because I personally prefer the glyph support - being able to pull out water elementals for the frost field and thus extra chills can be very handy in kiting unstoppable champions, or kiting, period, and the bonus heals from the bigger one doesn't hurt either.