With the launch of Sega's account service (as covered here), at the moment it's rather bare-bones.
What kind of features or services would you like from Sega Account?
For example, this is what I would go with:
"Arcade" page for browser games. And I don't mean cheap browser games like Sonic Heroes Puzzle, Sonic the Broad Jump, Sonic Knight In Training or Sonic Maze Craze. I mean decent browser games like Shadow the Hedgehog Flash, Sonic Rivals Dash or Sonic x Vapor (I'm putting the LEGO Sonic Superstars game as a good example also.) Given it's 2025, browser games have made a great leap since the 2D flash games we had in 20'00-10, so I don't see why the Arcade can't splurge out with 3D browser games on par with Sega Superstars quality of mini-games. (Also, the fact I bring up exclusively Sonic games are purely just for examples. The Arcade could have games for various Sega IPs if they want.)
For PC and consoles, Sega to release a successor to Sega Ages and Sega Mega Drive Classics, with the option to purchase additional games either with the providers' payment service or through Sega Account. Games for Master System, Game Gear, Mega Drive, Sega Saturn and Dreamcast.
Nintendo has Mii Studio, why don't we have an Avatar Studio?
Cross-accounts/account merging with other websites that are owned by Sega and rely on accounts that can be merged. Such as pso2.com or segashop.co.uk.