Server Browser for Custom Games?

Wouldn’t it be cool to look for custom games on a server browser in-game? For me, all of the maps I bookmark I play solo because most of my friends barely play Halo 5 and/or Xbox a lot. This would be a great substitute for split-screen and offline Custom Games. Also, this way game-modes such as: Castle Wars, Arena Warzone, Jenga, Duck hunt, Halo 2 BR Slayer, Forge (would be like GMOD Sandbox online), and more could be played online with other players through servers, without having to invite random people in a matchmaking lobby. Racing Online. Parkour Online.