One of my favorite games to stream is the TNA CE I purchased late last year. I have a redemption on stream to play the "Single reactor challenge", with the highscore holder having their name on screen (each TNA stream) until it's beaten by another attempt.
The single reactor battle is an unoffcial mode that Scott came up with and posted on his blog about a few years ago: https://www.scottdanesi.com/?p=1777
This mode is a lot of fun and forces you to play the game differently, while working within the same rule set of the game. Over time, I've been slowly pushing my score higher and higher as I make attempts on stream for viewers. In a recent stream, I dedicated the whole stream to the challenge mode and managed to break 1.6M for the first time - which is now on YouTube:
If you've not yet given this "mode" a try - DO IT! Simply set the game to 1 reactor and score as many points as you can before taking out the reactor. Sounds simple, but higher scoring becomes more difficult as you really want to destory the reactor on ball 1, in multiball, while having a max reactor value and pressing points along the way.
I'd love to see this added as a "Challenge mode" in a future code update - it's worthy of being an officially recognised mode. Similar to what we see with new Sterns these days adding in challenge modes. Being able to select this from the attract mode (like you would for team / co-op modes) would make it easily accessible and having it's own highscore table entry would make it something for people to grind away at and get better.
For anyone that's interested, you can watch the full VOD here with all (good and bad) attempts from the stream: https://www.twitch.tv/videos/1831405933
It's a great challenge - give it a go!