Flames: I like the idea to apply 2 fireburns at once, but why boost Flames when you may just want to reduce the physical damage penalty ? I find BURNDAYRAZ pretty powerful, and making this kind of change would imbalance casters further.
The problem I have with both this and the current flames is that it only appeals to a BURNDAYRAZ specialist.
Mana Leak: After that change, pure casters would be in a pretty bad shape. And what if I want to cast ENDISWAL to survive the next hit, then finish the monster with GETINDARE ?
If you're a level 5 character, then you need to pay 5 HP. Is it really any different than revealing one extra tile to afford the mana cost? If you need the health more, this boon is a bad thing. If you need the mana more, it's a good thing. It's the kind of tradeoff Mystera needs, particularly to give some BLUDTUPOWA alternatives to using her effectively.\
As for your suggestions, I feel they infringe heavily on Dracul's theme. In fact, Blood Hunger can
be used to gain MP on attack when combo'ed with BLUDTUPOWA.