As an example - that project bird I pictured above is generation 5 for me. Their father was a pure sebright with full lacing - and therefore these girls have 'at least' half the lacing gene compliment. Next round they'll be bred to another pure sebright with full lacing - so I'm hoping to get...
I think a Serama / Sebright crossing would be delightful! They're very similar in many ways so that would cut down your work if you were aiming for a return to Serama type.
From the Sebrights you will inherit:
Slate/Blue legs (featherless)
Henny Feathered tails
Rose combs
They are not as full...