The Bucks are pretty the San Antonio Spurs as in we have a Spurs Coach, are a small market team, and are best three players fit the archetypes of the spurs big 3 almost perfectly (Tim Duncan is a top 10 player of all time btw).
The role we will need Marjon to play will fit the role Kawhi when SA made back to back finals appearances, losing in 7 to the Heat and then embarrassing them the next year. I see no reason he can't at some point Marjon can't fill the role of taking on the heavy lifting defensively, shut down losers like Lavine, Booker, Tatum etc. and have a more limited offensive role where he chooses his spots. Whether or not he wins DPOY or leads a team on to a title is another project but he can at least play like young Kawhi.