Advice for maximizing MPR growth. (in New players)

As title says, is there anything other than targeting 100% challenge bonus opponents with PR close to mine that I should keep in mind?

Focus clan opponents, Higher their PR the better, higher your PR while still getting 100% the better, feel like there is something else but I can't remember it atm.

most of the clans i can fight are way down in the list for me. i have to train a bit longer in the 600k range but at the current rate of exp gain i have right now it will take a long time for me.

needless to say your growth is doin hell of a lot better than mine.

Well they are a NUB so their BA comes free. Their growth rate should be ~30% greater than yours, ideally.

yeah so viole take your NUB to its full extent.

Posting the obvious here.
Plan for xp bonus times and use your maximum amount of ba during those times, also avoid money bonus times and spend all your ba before. These are huge if used correctly.

Clan opponents give a hidden bonus, opponents within specific brackets of your pr give you a bonus (Don't ask me, only Natasha could explain it, I just understand the concept for the end game), Obviously hit all XP times with full BA and purchase your BA during that time, stay in a high bonus clan, after all that random factors play into it as well.

100% Challenge bonus, while great and I highly recommend it, don't focus on making that your main goal. There have been times that I've proven that a 20-30% challenge bonus vs the right opponent gave more then 100% did with others. If you pay very close attention to your XP gains you will see the random spikes, but certain characters will either be consistently higher or lower then others. You can use this to weed out your fight list to maximize your growth potential.

Now for my opinion on 4 minion strats...

In all honesty, the best growth potential for end results only comes three ways. First there is buying 3 minions at the end of the run, which is (outrageously expensive), second you could stagger the buying of minions to suite your exact end game needs based on which minion will be training what (also expensive.. and requires really good planning.. but wont get as high MPR results), and lastly there is the use of a RoE for the entire run while using either of the first two methods.

That's if we're strictly speaking "How do I obtain the highest MPR possible in one NUB/NCB run."