About pretenders I'd like to see more misc slots added to the actually very weak ones (and/or perhaps some 1 in one path become 2) like it was done for dom2.
I also think that indie mages and shamans are overpriced (the question is less if it's intentional but if it's a good idea if you want to have all units useful ; in most paths 1 isn't sufficient to make a booster and diversity doesn't really worth to pay 180++ gold for a -sometimes old- mage you'll have to empower anyway).
For light cavalry I would reduce the price instead of making it more effective (say 15-18 gp if the standard archers stay at 10). Reducing the cost would make fast defensive armies (sufficiently big to inflict signifiant casualties to a normal one) a viable strategy without reducing the friendly fire if you use light cavalry as a reinforcement for other troops.
I think the price of light infantry should be reduced a little too (say worse militia 5-6, ultralight/tribesmen/light without javelins 7, most light 8). With more ressources to build heavies the light troops become even more useless than in dom 2 (of course you have more gold, but who will make prot 6 soldiers instead of keeping it for castles and mages ?). And reducing prices for weak units is globally a better idea IMO than raising prices for usefull ones, as it gives more utility to national leaders (with smaller armies the actually rarely used generals would never be used).
PS : about horror marking I also support a big nerf. As it is you just need 3-4 S2 mages, a level 1 research and about 20 gems, to condemn a SC to chain death (see
the sad story of my pretender here)