They’re like wyverns in many ways, one of which being that most nothing will attack them whilst riding unless provoked. (With the exception of Nameless and Reapers, because they’re bastards). However, something important to note is that if you have a second passenger (since the saddle is a two seater) anything aggressive that wouldn’t agro on you before — now will. Not sure if this is a bug or what, but the passenger can also get hurt, so be careful.
Good luck out there, survivors.
If you Aim your mouse at surfaces it will show up a blue reticle, pressing left click with charge-glide you towards it. You can use this in any direction, including dive bombing on a creature. If you time your glide arcs, aim straight up, charge-glide and cancel midway you can gain more altitude and continue flying virtually indefinitely (Stam).
This thing is one of the BEST traveling dinos you can have, it can glide, climb, walk/run, and swim pretty easily! Not to mention it does decent damage, I recommend putting stam, hp, and melee damage on it. Use oxygen if you want to be underwater more often but it isn’t a good aquatic creature.