Well Primeguardian, actually, you lost much more than what you showed on your infirmary screenshot... Don't forget it's only 70% of you losses ! :D LOL
Anyway, I'm the feeling you're not exactly understanding the way Persians work...
1) The payout has always been basically the same amount as the investment, not 110%. However, it can fluctuate quite a lot : sometimes much more, sometimes much less, but in the end, what you didn't get immeditely with the old system was kept for later anyway.
The 110% mehtod was actually intented to gradually raise your payout incomes aas your armys grew stronger and you could afford sending more troops. It's more a mehtod to force globally higher rewards than an absolute need.
2) Now the new system just drops a few troops as you hit positions, and not only after you've re-invested 100% (or 110%). But you still have to add them all in the end to know what your total payout really was. You can't just consider only the (relatively) big payouts and just not ignore all the rest.
However, you should still be able to get an old fashion big payout, provided you managed to reach the 100% or 110% sweet spot without triggering any partial payout, i.e. not finishing any position until the end.
With the old system, you could afford to actually finish positions, as you got no payout at all most of the time, so it didn't have consequences on the bank. But now, finishing positions has, so just try not to finish any undtil the end.
3) Since you actually invested 100% to get 100% (average), the reason to Persians was not just a matter of getting lots of good troops for nothing. The idea was to build fresh, preferably cheap ones, and send them to die in order to get better ones. It has always been thought that way.
Sending loads of horses and phalanx, especially to small levels positions as you shown above, just to get others of the same kind, is clearly a bad idea. I do them with 80 to 90% light and heavy infantry and complete with a pinchful of phalanx if I have to fnish the position (for a quest, for instance).
It does take some patience (so it's a bit incompatible with those many quests and tournaments about Persians we now have more often), but then it works like intended : build cheap fodder from resources you get from raiding anyway and not from real money, send them to positions, earn horses and phalanx, keep them preciously. Don't waste bettter troops to just get the same kind.
I know it was previously usual to burn all you previously earned troops to get a bit more in the end, but I've stopped playing like this a long time ago, as it's too risky : I often ended up with less than I had to start with. Now I'd better grind them slowly, knowing that what I'm building will be lost, but keeping the good troops safe (actually for PVP use) rather than gambling them.
Actually, the main concern with the new system is the frequent resources drops that reduce pure troops payouts. However, even getting mostly small payouts, I'm still getting cavalry and phalanx out of investing infantry, so it's not 100% negative anyway, though it's less a fair trade than previously. But the fact my grain consumption is now strongly negative has to prove my troops numbers are globally increasing (though or course I'm still building some, but not as fast, and the infantry grows only to the point they get all sacrificed before building a new batch).
