So I'm building a bloodhunter and I've chosen the Order of the lycian. I was wondering how creative I could get with what my other half might be. Rules would be good but my DM is pretty lenient. If I were to make my own hybrid, how would I choose balanced stats and what should I base it off of? Thanks in advance.

I believe the context of this hybrid form is half-man half-wolf, i.e. a werewolf. Obviously you can substitute wolf for a were anything. I personally would advise you to be as creative as you wish in describing your hybrid. As for stats, the class feature for "hybrid transformation" specifies; something like bonus to damage, strength check advantage, resistance to some damage an AC bonus etc etc. - that's what you get and, RAW, all you get. 

creative suggestion, a wereboar, and the hybrid looks like a sickly mutant orc! at least to the locals. Lots of great story potential there, does your character speak orcish, I wonder?

 Thank you! This was very helpful. I had no idea and I'm quite liking the suggestion you had in mind, very good for the whole blood hunter "everybody hates me" side of things and goes a lot deeper than just being furry boy.

The way the Hybrid transformation is designed, is that the hybdridation, can be anything really, the rules and benefits you get are pretty much the same in all cases.

In my case, My Tiefling Dark Knight( Paladin/Warlock) who got to Avernus, started to develop some blood magic abilities after a while, so iw ent for Order of the Lycan, and fluffed it as His Devil Blood been more dominant in its natural habitat, so when he shifts in his Hybrid form, his horns grows larger, spikes grows out of his back and arms, he grow larger and his tail as serated blades coming out of it.

Think of it like DMC's Devil Triggers, but from a mechanic and rules standpoint, its the same as a Lycan.

Im working on a were-ape blood hunter lycan and this was the same thing i was wondering. Im hoping i can add maybe some climbing speed or athletics to my build when he's transformed 

RAW, this is what you get, no matter what the beast side of you may be:

Hybrid Transformation Features

While you are transformed, you gain the following features:

Feral Might. You gain a +1 to melee damage rolls. This bonus increases by 1 at 11th and 18th level. You also have advantage on Strength checks and Strength saving throws.

Resilient Hide. You have resistance to bludgeoning, piercing, and slashing damage from nonmagical attacks not made with silver weapons. While you are not wearing heavy armor, you gain a +1 bonus to your AC.

Predatory Strikes. You can apply your Crimson Rite feature to your unarmed strikes as a single weapon. You can use Dexterity instead of Strength for the attack and damage rolIs of your unarmed strikes. When you use the Attack action with an unarmed strike, you can make one unarmed strike as a bonus action.

Your unarmed strikes deal 1d6 slashing damage. The damage increases to 1d8 at 11th level.

Bloodlust. If you begin your turn with no more than half of your maximum hit points, you must succeed on a DC 8 Wisdom saving throw or move directly towards the nearest creature to you and use the Attack action against that creature. You can choose whether or not to use your Extra Attack feature for this frenzied attack. If there is more than one possible target, roll to randomly determine the target. You then regain control for the remainder of your turn.

If you are under an effect that prevents you from concentrating (like the barbarian’s Rage feature), you automatically fail this saving throw.

Anything beyond that is at the DM's mercy. 

I have to ask, how would using the Aasamar transformations work with the were powers of lycan? do I need to deactivate lycan to use aasamar?

Class and race features stack. Unless they explicitly say otherwise ( druids wildshape is the only one i am aware of).