TLDR:
Total penance points available:
90+460+450+450+470+405+335+500+570+1260
=4990
Total points expected after 400 missions played (100 missions per class):
90+460+450+450+470+345+335+375+550+1260
=4785
So if you started playing now, you would likely be able to get all the way through the penance point reward track (maxes at 4500 points) by the time you have played 100 missions with each class.
Considering that this would leave you with 285 points over the 4500 threshold, you would probably be done after playing ~75 missions per class.
I might have a counting error somewhere, but here is what i got for each section:
Account (90 points)
Level all 4 classes to 30 and you got them all
Classes
Veteran (460 points)
Zealot (450 points)
Psyker (450 points)
Ogryn (470 points)
Play 100 matches with each class and you got them all.
Some penances require you to use a specific blitz/ability/aura/keystone.
It takes about 10 matches to complete each of those penances (some can be done in a single match).
Each class has 3 options for blitz/ability/aura/keystone.
Since you can do the penances for one of each at the same time, you would have to play around 20 of those 100 matches with builds that are different than what you would usually run with.
Tactical (405 points) (after 400 matches, probably 345/405 points)
After playing 400 matches (100 per class) you can expect to have completed most of these.
You will probably miss 60 points due to these penances not being finished (click to expand)
- Up and at them requires you to help downed allies. Within 400 matches, i would expect you to have helped more than 100 but fewer than 500 downed allies .
You lose out on T4 and 5, which are 5 points each.
(-10 points)
- War’s not over requires you to rescue allies that have been killed. Within 400 matches, i would expect you to have rescued more than 50 but fever than 250 allies.
You lose out on T3, 4 and 5, which are 5 points each.
(-15 points)
- Purge the heretic requires you to kill enemies. Across 400 matches i would expect an average of ~250 kills per mission to be achievable. That sums up to 100k kills, which is enough to get T3 of this penance. You lose out on T4 and 5, which are 5 points each.
(-10 points)
- Situational awareness requires you to blow up enemies with explosive barrels. Across 400 missions i expect 500 barrel kills to be reasonable. 1000+ seems a bit high, so you miss out on T4 and 5, which are 5 points each.
(-10 points)
- Discipline and teamwork requires you to deploy ammo crates and medipacks. Deploying 250 over the course of 400 mission seems very achievable. Deploying 500 might be a bit too high, so you miss T5 of the penance, which is 5 points.
(-5 points)
- Dream team requires you to complete 100 missions without anyone being downed. That is probably an unrealistic expectation for the first 400 missions played, so you are not gonna get those 10 points.
(-10 points)
Heretical (335 points)
After playing 400 matches, you should have all of these.
Missions (500 points) (after 400 matches, probably 375 points)
After playing 400 matches (100 per class) you can expect to have completed most of these.
You will probably miss 125 points due to these penances not being finished (click to expand)
- By doing 400 missions, you will obviously not have completed 500 missions, so you skip the last tier of Atoman auxilia.
(-5 points)
- You will clear each objective type around 50 times. There are 7 primary objective types. You will miss the penances for 75 and 100 each, which are 5 points each, so -10 per objective type.
(-70 points)
- You will likely get at least 50, but not 100 hacks, as well as more than 100 but less than 200 auspex scans. You miss two penances (one for each) which are worth 5 points each.
(-10 points)
- If you pay some attention to it, 400 matches are probably enough to extract with 60 scriptures and 45 grimoires. You will skip the last tier of both penances, which are 10 points each.
(-20 points)
-You will likely not clear 30 missions each with Vent purge, pox gas and power outage condition. Probably also not 50 maelstrom missions.
10 of each condition and 25 maelstrom missions seem very realistic though. You skip the last tier of each of the 4 penances. and lose 5 points each.
(-20)
Exploration (570 points) (after 400 matches, probably 550 points)
After playing 400 matches (100 per class) you can expect to have completed most of these.
You will probably miss a few points, due to not having played 50 missions in every single region.
25 missions played in every region is to be expected for sure.
You might not clear 50 in around 4 regions, which loses you 5 points each (20 points overall).
Endeavours (1260 points)
After playing 400 matches (100 per class) you can expect to have completed all of these.
You just need to play all 18 missions on Auric damnation difficulty, at least once.
Edit: fixed a mistake in the calculation