Arsenal still have a lot of work to do in this summer’s transfer window. The Gunners turned David Raya’s loan into a permanent deal early in July before completing the signing of Riccardo Calafiori from Bologna. Reports have claimed that Mikel Merino is close to joining Arsenal, and we think he would be a great signing if the deal goes through. However, the Gunners need more in this window. Reinforcements in goal, attacking midfield to replace Emile Smith Rowe, and in attack are still a necessity, and Edu Gaspar and Mikel Arteta could pull off some smart deals if they decide to bring a few ex-…