Half way (in General)

So seeing as I just got halfway through my NCB just a few days ago I was looking for some criticism of how large I am. Being my first NCB I don't know where I should be at score/MPR wise. Finding targets isn't easy, though most of that is attributed to a large number of the characters above me being retired. My weapons aren't quite up to par either but once I come across some extra cash I'll deal with that. Right now I can keep my challenge bonus at least above -10% with a handful of my targets giving me a positive, just looking for some feedback!

Highest MPR in game is ~9.23 mil, and the N*B was allegedly designed in such a way that if you fight normally with all possible BA (that includes the daily purchasable/collectible ones) against very good targets you can reach about 95% of that at the end while growing nearly linearly (so, right now, at almost best you could hope for 47.5% of that, or ~4.38 mil MPR).
Now, obviously, people do miss naturally regenerated BA every now and then, and not everybody can afford to buy much (or any) BA during a NCB run, so realistically speaking, we could easily drop to 1/1.35 of that again - so realistically speaking, with optimal target selection and no BA purchase, you could have gotten to ~3.25 mil MPR.

Your growth was fairly linear so far (except the initial saved-up-BA push to ~150k or thereabouts, the graph is almost straight), so it means you generally fought opponents of similar relative difficulty level throughout most of your run so far.
If you continue the same way until the end of your NCB, you'll most likely end up somewhere around 4.8 mil MPR (plus-minus 0.1m), which is not quite 6/20 (you'd need a bit under 5.54 for that).

You should have a higher challenge bonus..

I believe you could do a few things slightly different than you are doing now.

1. drop your net wt of things that are ineffective right now.

Like use only 2 pair of db boots one in front one in back.
have your corn on your AB caster unless you have the hp to let your GA do all the work.

Drop the AoJ your using a RoS
I bet the AoF would be way better all the enchants you are using but they have a drawback also.

Seeing as i am not sure where your kills are coming from do you take more damage from other GA with 4 Archer witch is a cool way to go.

Or do they do more damage than the return GA if those are some of your targets.

With an archer team are you targeting CoC, Decay, EF, BL teams that have to get to melee before doing a ton of damage. Sometimes you can climb really high if you find the golden target.

Look for anyone above you using your strat and see who they are hitting maybe you can beat one of their targets or at least see the strats that they are winning against.

Maybe for the short term focus on upgrading one bow and using your other minions as damage sponges to dish out some of that GA damage
till you can start pumping up another bow.

There are some spots where you just have to plow along.

Hope you have good luck with the second half of your ncb.

Thug

PSing

You might try stripping your minions of everything but there bows and RoS and see if and how many of your fight list you can beat that way.