I do believe that most recent patch changed game for the best. Overall nerf of ranged enemies and armor from trash parry allowed melee to finally shine and almost no dodge spam required anymore (thank the Emperor!)

However,
The game became too easy. Now you easily beat any Ruthless Operation not only without dying, but without injury at all. Maybe 1 armor for each trash parried is too much, maybe it can be half of armor, or less. But even without parry spam, for example when playing heavy, it's too easy.

I don't want changes to be reverted, I think most of them are for the best. The game before felt unfun and unfair, ruthless required cheesy playstyle to consistently win. Now you finally feel like a space marine, when you're not so afraid of small enemies. But I do wish some new additional tweaks to be done to Ruthless difficulty to make it more challenging. For example:

1. Evil​er Game director (with ammo boxes adjusted for that) - if you look at Darktide's max difficulty for example, game director there sometimes (a lot of times) behaves completely unhinged throwing every single enemy type at you at once in swarms with bosses and specials on top - and this feels AWESOME! Spacemarine2 director is toothless in comparison. Most often than not boss enters arena without any enemies to support it, and only one special hits the field at a time. This is too easy for ruthless difficulty, let director be more evil, to pose a challenge for seasoned players and bring more variety to missions.

2. More frequent encounters (with ammo pickups adjusted for this as well of course). Again, Darktide's max difficulty means that your mission is basically one continuous fight, with very rare moments of reprieve. In SM2 it's almost other way around. Waves are rare (especially if you cut down reinforcement cries, which you often do, if you're a seasoned player), and they are smaller and shorter. Let us be on edge throughout the whole mission clinging to our own lives and each other's, to search for ammo and pickups not in silence after everyone is dead, but while fighting off angry hordes.

3. Mission modifiers. On top of those two, it would be cool to have some random modifiers applied to max difficulty. Like more elites, or thicker trash mobs, more trash mobs, more frequent specials, minibosses on top of actual bosses ​(yes most of these are from Darktide as well, but damn it all works wonders there!), or something in that line.

Some such changes are desperately needed, because as of now max difficulty can be easily beaten with almost no injury. At the same time, I feel like some bolter weapons need a buff should the game become more difficult, because those seem to struggle to be relevant the most, even now. Personally, I've grinded most of the weapons and classes some time ago, and the only reason for me to go on Operations further is to get my butt kicked so to speak, and I think that would be true for many players as well.

Ha, yeah you could artificially make it harder by hindering your loadout, true :) And I have very high hopes for upcoming difficulty, as well. I do hope that will be something unique, never before experienced in operations. But it can be months until that moment. Meanwhile at least some tweaks to Director behavior and quantity of enemy waves could go a long way to make what is currently there a much more thrilling ride.

This is true.  Immediately upon update Ruthless became easily done solo.  To make it better there just need to be twice as many enemies with the same level of difficulty.  Maybe even 3 times.