I tallied up the entire roster's stats in a spreadsheet to see how they compare w/ each other and Krillin is the lowest at 13 points while Kid Buu is the highest at 19.

How I did the calculation is I grabbed their stats based on power, speed, reach, technique, and energy and added them all together to equal their number. I took the stats off the scans as I saw them.

SS = 5 points, S = 4, A = 3, B = 2, C = 1

Krillin's Score:
Power: 2
Speed: 3
Reach: 1
Technique: 4
Energy: 3
Total: 13

Kid Buu's Score:
Power: 4
Speed: 4
Reach: 3
Technique: 4
Energy: 4
Total: 19

This isn't to say Kid Buu is top tier and Krillin is low tier. For example, Android 16's final score was a 14, but because he's the only character in the game w/ a OHKO, that makes him top tier. The scores are just data to show the combined stats of all the characters in the game so far.

Here's a link to the screenshot:
https://i.imgur.com/N0K0igj.jpg

For DBFZ:
http://gtm.steamproxy.vip/app/678950/discussions/0/

Source:
https://www.youtube.com/watch?v=CGAJMNi6ryg

https://www.youtube.com/watch?v=F-E4qu_QxQ4&list=TLGG3NAeCe9GXVsxNzA2MjAxNw

https://www.youtube.com/watch?v=PCxRTqwM35w