I gave around 20-25 exp per session using the GM Kit module.
I'd prefer you to comment on my other point - do you think a level adjustment is fairer if it essentially means you need to get 225 xp to get level 1 (+100 Dp that is)which is 125 different instead of it being only 25 xp more.
I assume you mean to get to Level 2, rather than Level 1 (which needs 0xp), but anyway that's just me being pedantic.
The mistake I think you're making (sorry if I'm wrong) is in thinking that they only pay a 25xp penalty. They don't. They pay 25xp PER LEVEL
more than usual.
By the time they get to, say, Level 10, they'll have needed 225xp more than a standard character who neither has a Legacy of Blood nor is a different race. Their teammates will be over 2/3rds of the way to Level 11 by the time the Legacy gets to Level 10.
From Level 6 onwards, they are a whole level behind their teammates more often than they are the same level.
That's a reasonable penalty to pay, I think.