This is the breakdown of Gomes' minutes and employment this season thus far.
EPL - 1 game (9 minutes total) versus West Ham. United was 1-0 down and playing poorly, so, he came into a poorly functioning side that day. He was substituted on for Mata, however, instead of taking AM, the previously substituted Lingard went central and Gomes was reduced to playing wide left for those limited minutes.
Europa League - 3 games
vs. Astana (h) - Played 68 minutes in his natural AM slot alongside Chong and Greenwood.
vs. AZ Alkmaar (a) - Played the full 90 minutes, however, on the left side instead.
vs. Astana (a) - Played 88 minutes, however, on the left side. Side featured Laird, Garner, Levitt, Chong and Greenwood.
If he hasn't impressed in matches, contributing factors to that could be either that he's not playing in his natural performing position, or that he's not playing in first IX's that are anywhere close to being full strength. It's an argument that has to be taken into consideration. Greenwood has done superbly, however, he has had the benefit of playing with practical full strength United IX's. Gomes, on the other hand, has had to try to impress in teams with lesser overall quality.
It'd be disappointing if he leaves, to be honest. He'd end up a team like Dortmund or Leipzig, in AM, and developing playing in a correct position. I have a feeling that down the line, we'll regret not securing his contract.