Animations:
1. Pitching animations tend to be slower than in real life. The animations need a bit more speed. Maybe time for a game speed slider?
Visuals:
1. See more emotions in the game like players reacting to error on field, making a impressive play on field, pitchers not getting the calls they want, batters not getting the calls they want.
2. Teammates in dugout chilling and cheering on their teammates who are at bat or on the field.
3. Show managers mad/yelling about a certain call that the umpire made.
Commentary:
1. Smarter and deeper level of commentary. The commentary is the same in every game. Maybe update the commentary every few weeks. Madden did this.
RTTS:
1. Increasing overall should be faster. And caps should be removed. It's nothing more annoying than trying to increase a skill but it's blocked with a cap. Old school style of upgrading what you want with skill point.
2. Ability to call your agent whenever and not just in between the season or off season. (example: demanding trade immediately, changing to any position, speaking with media). In real life players have full control over their careers .
3. Switching positions to the one you want instead of the suggested one (example: changing from pitcher to outfield, catcher to infield, outfield to pitcher, etc). In rtts we can't change our position, the game chooses the position for us.
4. Interviews with media that influence teammates to play better, encourage more fans to show up, boost team sales, boost team attraction for free agents to sign with team, etc.
5. Make contracts actually mean something (example: buying different style jewelry, upgrading player skills, buying a house, car, personal chef , or trainer.) Like as you get better (more money) in the league you go from apartment to condo to home to mansion. Almost similar to GTA . The more top rank and money you make the better lavish your living situation is.
6. Asking management to target certain players in free agency as well as asking management to keep certain players who you enjoy on the team like in 2K.
7. Apartment, condo, or home in rtts would be cool cause let's be real players aren't in lockerooms 24/7. Also would be cool to see actual rings/trophies/awards our rtts player has earned like in a trophy/display case.
8. After awhile of playing RTTS I found dynamic/boss challenges and player skill increase/player relationship icons intrusive during gameplay. These things should be more subtle, or optioned to be turned off. It makes rtts gameplay seem more arcade while playing on field.
9. Keyword is control. I feel like letting the user have more control over rtts player would make it more fun on field and off field. Checking social media, talking to media like MLB Network, signing sponsorship deals to a brand, upgrading apartment to mansion, using contract money to buy tattoos, clothes, cars, equipment, hire trainer for offseason to boost overall, etc. Maybe some of this over the top but you get my point. 
Accessories:
1. Fix the jordan 1's. The coloring on the top flap of the shoe should match the red color. And can we see shoe laces tied now?
2. New elbow gaurds
3. Baserunning mitts