I might be the exception, but I loved 7e GW and ran a successful "long-term" campaign with it (meaning it went on for several months and the characters reached max level). It's probably my preferred way to play using the base 4e mechanics.I played a lot of 2e GW, and loved 3e. The Techno Knight on an armored mutated feline, on the 3e GW is a classic piece of TSR artwork.
7e GW, while I appreciated, how quickly one could jump into the game, felt like a one shot style game, not something that would sustain a long campaign.
Arcana of the Ancients, a Monte Cook Games product could serve as the basis of a 5e based set of rules for GW. It covers mutations and has hundreds of Techno-Magic...and for 7e GW lovers is partially written by Bruce Cordel.
I might be the exception, but I loved 7e GW and ran a successful "long-term" campaign with it (meaning it went on for several months and the characters reached max level). It's probably my preferred way to play using the base 4e mechanics.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.