I've beaten a couple planets so far so here's my feedback so far:
Enemy levels and tankiness generally feels good
The shield buff should be removed from the Treasurer since he already has high shields that cannot be bypassed with Toxin and provides extremely high damage reduction.
The higher spawn rates feel good except in missions like interception where it makes defending points difficult.
Teshin's store needs more rewards added to it overtime to give reason to keep playing. Things like exclusive mods, forma blueprints, more cosmetics/decor. Personally I'd buy pre-built apothics.
Steel Essence seems to have a pretty low drop rate, so the price of things like relic packs means it is far more practical to just passively farm syndicate standing. This is especially true considering most people playing SP are likely above MR 20 and can get a relic pack worth of standing a day with just a sigil.
Rotation rewards need adjusted. There is currently no reason to stay for more than one rotation for players who want the rotation rewards.
Steel Essence drops should be increased. It shouldn't be possible to fight a Syndicate eximus squad and not get at least 1 essence.
Nerfing the Xoris makes me feel like I have less player choice rather than more due to other stat sticks requiring Naramon + Rivens + Combo Mods.
Since the Xoris is tied to a low-MR quest, Khora is accessible after the completion of The New Strange, and Xoris doesn't require a riven due to its dispo being 0.5, the Xoris was a very accessible stat stick for newer players who don't have access to focus/Naramon, but do have access to some gladiator mods and a low MR glaive.