I figured this would be relevant per the release of all the salary data this week.
As always, drop suggestions in the comments, happy to make adjustments.
Below is a way to easily show all of the players in MLS and what they make. If you select a club it will highlight all of those players (since Chicago is at the top alphabetically, it looks like they dominate the viz at first glance). You can also filter to a specific club if you want to see their avg salary data by using the drop down in the upper left of the scatter plot.
Below the scatter plot is a box plot that shows the average guaranteed compensation by team. NY, LA and Toronto far outpace everyone.
This visualization shows which position cumulatively pays the most and how much each team spends on it. If you select a position or club on the legends it will highlight them. Note that MLS classified the positions in a very odd manner, I wasn't sure how to classify some of the combos, so I left them as is since Forward (F), Midfielder (M), Defender (D) and Keeper (GK) were all standard.
Lastly, this shows the top 50 vs bottom 50 paid players in MLS, you can filter by club using the drop down on the right.