I love this idea. Also, other suggestions for people who can refer/vouch: people you've worked with in inter-house challenges(like the new QWC match that's going to happen, and the challenges in the Great Hall), or even the various challenges in your house(I don't know much about the other houses, but I do know that 'Claw has a lot of these going on at the moment); your beta who you've worked with for quite some time; your gauntlet guide; people you've worked with in the BA(or the BA mods themselves) etc.
While I like the idea of being recommended, could you perhaps do it like you do a referee on your CV? Like, if you're in the SBBC, you could get Natalie or Julia to vouch for you. Someone who has also accepted/worked with you, and at least knows your abilities, rather than a random mod or something who mightn't know you at all. I'm not sure. Something like that? Maybe if you participated in a QWC, you could get your Captain to vouch for you.