As to the MIA offer, as reported:
Herro, Ware, Jaquez, 2026 1st, 2 future firsts
First, this doesn't even work in terms of salary matching. MIA has to include $3.7M more and then it is a 4 for 1 trade. MIA has to fill up their roster after. I see Ware as a decent prospect. Herro I see being flipped so it is a projection of what you can get for him in terms of young players and picks, which may not be much ($33M is a big contract to trade). The picks are good not great, probably get you middle class players like Ware. The fit for Giannis with what is left in MIA is poor.
Compare this to say Brown, or what MIL could get for Brown in a 3-way or a separate trade. POR makes the most sense as the 3rd team but ATL could offer a decent package also. If BOS has in fact made an offer to MIL, it is probably a deal favorable to BOS, but less than what MIL would ultimately take.
There was a report from Ira Winderman on Sun Sentinel and some tweets indicting it's that package + Jovic. Jovic makes about 4.4M. Still, he's 23 with potential but the Heat didn't even use him much last year so makes you wonder. I believe Miami's future picks are also after 2030, which may be fine but MIL might covet a few picks and younger assets sooner as well.
I still think he'll end up in Miami. I'm a bit iffy about this overall reporting in recent days since the Celtics usually work in silence, and I think MIL is just holding out hope for now that other teams jump in but this Miami offer is their "safe route". Herro, Ware, Jovic, Jacquez, #13 + 2-3 future FRPs. But otherwise Stevens and the organization wouldn't just be leaking info and rumors to people like candy, IMO