Set up multiple artboards for all of your different assets for a team.  
It makes exporting way less of a pain. Especially when doing different color variations for different uniform sets. (You can improve that workflow by using global colors, too)

My standard artboards are 1500x1500 (1000x1000 would be plenty, too)  
I find full square logos work the best in the editor when scaling.

The only deviation from this is the Artboard for the Postseason Endzone.  
Its sized 2048x383

  
When you go to export:  
Export As > PNG  
Then make sure you select "Use Artboards"  
From there you can select All or a Custom Range  
All exports all of your artboards at once.  
(If you name your artboards, they will export as your file name + Artboard name)

Next, on the "PNG Options" screen you MUST select "Art Optimized" for the Anti-aliasing option.  
If you don't do this, you will have weird gray fringing around your logos on the site and in game.

Screen (72ppi) is your best bet for resolution.  
EA Teambuilder compresses anyway, so if you go more than that, it will just make you run out of upload storage faster.

This exact Illustrator file in the post can be found here if you want to use it as a template.  
[MAVS - Adobe Illustrator File](https://drive.google.com/file/d/1_hh7YLlgJiQ1SXWkk6HvJc1gNR-DPqox/view?usp=drive_link)

This is the Illustrator file for my most recent upload.

I'm no master of Illustrator or anything, just trying to share what I've found that works for me.

Enjoy!

Pro tip for those of you that use Adobe Illustrator