As an addition to the Halo 3 and Halo Reach Forges and to the occasional additional map added to these games, I was thinking that 343i could make the Commando from Halo Infinite for these games as a cameo appearance for when Halo Infinite releases. I know that this is silly idea but it’s one I came up with and I decided to put it out there.
The most they should do is add the weapon variants from Halo Online to Halo 3’s forge, with the only new H:O weapon that should be allowed to appear on a new map by default being the Default H:O DMR since it’s not a variant.
On that note though, ironically enough one of those DMR variants was essentially a commando anyways iirc, so you would be getting a commando in Halo 3 still.