BR performance with 2011 mini server: your experiences?

I have so far watched some blu-ray movies on my 2011 mini server. I wanted to see if you guys were experiencing similar performance.

Most movies were ripped to the HD using MakeMKV. These seem to run fine, occasionally the fan spins up but I think after a few minutes temps seem to stabilize and the fan lowers to a higher-than-baseline but steady level.

However I noticed that there seemed to be a difference between streaming the movie from the disc (MakeMKV streaming server + VLC) and ripping it to the HD. Occasionally the video will be very choppy while streaming, but after about a minute it steadies out. But maybe 5-10 minutes later it starts up again. These periods do not seem to correlate with the streaming buffer running low either. Playback from files ripped to HD don't seem to experience this problem. Is the extra load of streaming+playback too much? Doesn't seem logical but it almost seems that way in my experience.

Also have you guys had experience playing back interlaced video on the mac mini? A good amount of the movies I tested (all from the BBC Natural History Collections) are VC-1 encoded 1080i content. This won't play back in VLC so I had to transcode them on Windows. However, for a few of the videos they are AVC 1080i content. I enabled the deinterlacing processing in VLC and set it to Yadix(2x) but it really makes the fan spin up, and becomes distracting. Anyone have similar reports?

I tried Plex and I think at least part of the problem might be VLC. I noticed that the CPU usage playing back the same videos in VLC was significantly higher than Plex, at least double.

In addition, the fan spins up really high when I played back some of my videos in VLC- I used SMC Fan Control to set the minimum to 3500rpm and it still couldn't keep the temperature under 90C. It would slowly rise through 80C and eventually hit 90C when the OS automatically starts ramping up the fan to cool it down, it would go to above 4500rpm and the temp would drop to around 80C, but then it would go back to the minimum 3500rpm and slowly rise above 90C again...

I will test again with another movie in Plex but I don't think I will have those same issues. Only thing is, I find Plex to be terribly confusing as a player. I don't want a media server, a media library, or any of that- just the ability to play back individual files that I temporarily rip to my HD, or as an alternative, stream direct from MakeMKV. Can Plex do that?

What's strange though is that even in VLC, the total CPU usage isn't reported to be any higher than 75-100% (on a quad core i7 w/hyperthreading, the theoretical maximum would be 800%). Does this mean that if the CPU were to hit the maximum 800% say encoding in handbrake, that the mini would be hopelessly undercooled? I mean it could barely keep up with just "100%" load...

I'm thinking of tearing the mini apart and re-applying the thermal paste on my own using AS5 or similar, to see if the heat situation would be helped at all but I'm also concerned that it would interfere with my AppleCare warranty.