I'm fairly certain if Calgary put Gio in play this draft, they could easily get pick 3-7 straight up.
Don't be so sure, a 1-year rental of Gio would not bring in the #3 pick, as there would be zero motivation for Arizona to do that.
And it has notohng to do with Gio's talent level. it's just that teams with pick 3-7 are rebuilding, and Gio offers little to them beyond ensuring that they suck just a bit less next year.
Now, if Gio would agree to an extension as part of the trade, it would be different, but still, for the most part, teams that are rebuilding don't look at Gio the same as a contnder or near contender would.
If you think that Calagry is still in its rebuilding stage, Gio's best value to Calgary may still be in a trade, if the alternative is to sign him to an 8-year, $64M contract.
I could imagine that it might be near impossible for calgary to trade their captain, but he is quite a bit ahead of most of Calagry's other players in terms of tenure. In fact, the same argument applies to Hudler.
I expect that Gio will sign for 6-years, maybe $42M. Or 5-years, $37.5-$40M. If they can get him for 5 years and less than $8M, you have to be happy. But at what amount do you start thinking trade?