I agree, we should be able to download more content, but on the other hand, it's probably the best thing Yuke/2K has done for the servers. Given SVR's horrendous server history, it was hard to get any downloading done without getting kicked out to the menu right after or during a download. But that's just my 2 cents on that aspect.
Moving on, I feel there should be more social media in MyCareer/Universe mode. As much as WWE emphasizes on being connected with social media, one would think it would implicated in the game. Things such as in-character tweets/online-in ring feuds, injury updates, match updates, big announcements, post-match/show reviews/reactions. Something very similar to NBA 2K's social media.
Another thing that would be a nice touch is an in-game podcast. Seems to a money maker with Austin's, Jericho's, etc. Mini interviews, statements, announcements, etc, anything that revolves around what's happening in that universe or career mode would be cool.
A kickoff show for PPVs would be a nice addition. Just like the real show, topics would be about tonight's matches and rivalries (skipping the show is optional of course)
Can definitely use a MyGM mode. Emphasizing on being the GM, making matches and decisions that can cost or make you money. With a rating grade of the show, the better, the more money. The more money, the resources at your disposal (contract signings/re-signings, trades, bigger matches at PPVs (Cage, Cell, Chambers, TLC), championships, promotions, venue purchases, movies, etc.), the worse the show, the less resources, with the potential of bankrupting the business. Not to mention a must have of keeping your show's superstars happy. Happy employees are good and hard workers. The unhappy ones feel more reluctant to put on a show, or may break kayfabe, potentially costing you revenue and your job as GM if things get out of hand.