I like Milwaukee's chances against Miami without Giannis. They are at least on a par with Miami without if not better given that Miami will be without Herro.
G: Jrue vs G Vincent
G: G Allen vs Straus
F: Middleton vs J Butler
F: Portis vs C Martin
C: B Lopez vs Adebayo
That Middleton vs Jimmy matchup will be one to watch. Jimmy is clearly the better player but Middleton is a very good in his own right. Jrue with a big advantage in the backcourt. The SG matchup looks even.
Portis should give an advtange to MIL at PF with stronger team D and rebounding. Not convinced C Martin has the skill-set to create an advantage offensively depite being smaller and as a true SF should be more skilled than Portis - but not convinced. The Lopez and Bam matchup is interesting. Lopez has matchup advantages with his size in the low post and his range on his jump-shot while Bam has a quickness advantage. I reckon Brook can exploit his advantages better than Bam can.
G: J Carter vs Lowry
G: W Matthews vs Oladipo
F: Ingles vs D Robinson
F: Crowder vs K Love
C: M Leonard vs C Zeller
Not a lot going on on either team's bench here. Losing Portis to the starting lineup is a big blow to MIL's depth. Lowry could give MIA an edge at PG. Oladipo hasn't played much this season but I like his quickness against old man Wes Matthews if Oladipo is given the nod. D Robinson looks a neutral matchup against Wes or Ingles and is probably the more likely to get playing time given that Miami is down a shooter in Herro.
Kevin Love is a wild card for Miami. I trust Crowder more than Love in terms of consistency / dependability but Love can be explosive. The Meyers Leonard vs Cody Zeller matchup will be ... disappointing. I wouldn't be surprised to see both teams avoid playing these guys and just go smaller with Love and Portis playing center when Brook and Bam are resting.
I'd rate that Milwaukee team as a 40-45 win team without Giannis. That is a solid squad. That is aroun the level Miami has played this season. I do not see MIL as overmatched without Giannis. I see this as a fairly even matchup.