I'll admit I looked at the scans and I saw it mention that the perks may be hard to get if you are a higher level. I was planning on bringing my 81 mage in but I'm not sure if I should now because I won't be able to get the perks with him. I was wondering how much the new vamp/werewolf perks would increase your level by, or if it would even increase the cap at all.
Or doing the *spoiler* companions questline to get the werewolf form for the extra levels, then remove the curse at the end and get to a vampire and get those perks as well? Or would bethesda only limit you to one perk tree between the two?

You get perks for the vampire tree by feeding.

But does that level up your character? Like how casting a fireball increases destruction magic, which in turn contributes to your overall level. Or is it completely seperate? It seems like an odd sacrifice if we are investing in perks that require level-ups, yet the perk trees dont offer the ability to increase our level and provide perk points.

Wish it was allready in the game atm as the amount of necks if bitten had hiv like 7 times.

It doesn't level up our characters nor does it take up conventional perks. You gain the perks by feeding, this was done so that high-max level characters wouldn't miss out on being able to max the new tree.