Feedback on respawning, testing and XP systems

As you may know, the game is currently in beta. I am looking for ways to improve the game to make it more enjoyable (mainly orientated toward the non-containment breach side of the game.)

Respawning System

The current respawn system will spawn players in by groups on a randomized timer, Ex. If 5 players die before the respawn timer hits zero, then once the timer runs out, the game will respawn all players all at the same time. This might work for the containment breach side of the game, however I am unsure if this should be kept this way for the non-containment breach side. 

Testing system

The testing system added in version 0.4.0 was created to add an objective while playing as a scientist or guard when there is no containment breach. However, I feel like it could use some improvement.  The test session works by first having the player choose an scp to test on. Then, it sends a request to all players to join the test. Once there is at least one scientist and guard, it will pick a random class-d to join the test. Then, the test will start. The scientist(s) and guard(s) have 65 seconds make the scp either damage or kill the class-d. Otherwise, the test is considered a failure, and no XP is granted. 

XP System

The XP System was added in version 0.1.0 (0.1 in the devlogs) as a rewarding system for players to get better health and items as they progress. It also included a leaderboard UI for when you are a spectator. Although there won't be any significant changes to it, I am looking for minor improvements to it to make it better. 

If you have any suggestions to do with these three systems, then let me know either in the comments of this post or on my discord server.