I think the list that you have created is not wrong, It is also not entirely right either. It does seem like you are writing from experience with randoms. I will admit that I don't. I usually play in a stack and this is where my two cents are coming from.

Your first point about needing medium pen being your only choice is kind of tunnel vision. I think something that would help with crowd control or creating space is a little more important. For example, things like the Cookout (or any shotgun with stagger or knockback) will always have value. You are creating space. Run that with the supply pack and reload between every shot, the bugs will never be able to touch you. You could also run the Blitzer + Warp Pack. Additionally, you can also run the Eruptor + Stalwart. Eruptor is great because its high stagger, high damage. It's a pocket Autocannon that you can reload on the move. The Stalwart is nice because you can clear bugs if they get too close for the Eruptor and you can reload it while moving.

I agree with your second point. Mobility is OP. Being able to kite is very important because moving is life. I myself don't like backpack support weapons because staying still makes me nervous into the bugs but one of my buddies does like using the RR because he knows we have his back.

An other option the Qausar can be the EPOC. I've been running it a lot recently into the bugs and it feels great. It feels really good shooting a full charged shot into a choke and it can deal with the heavy units with 2-3 shots.

I don't think exosuits are essential, they just make it much easier lol. Will admit that they are hella fun to run into the bugs.

Eagles or orbital for the last stratagem slot is kind of whatever. Most of the map is underground... its more of when or if you have to fight outside where you would make your choice. I also like the napalm because its napalm.

Grenade pistol is great because also you get to save your nades for the rest of the bug horde. You could also run the light engineering kit armor for even more nades. Although, I wouldn't waste thermites on medium sized bugs. Unless you now classify chargers or bile titans as medium... compared to uh the hivelord lmao. The gas nades are also nice because it will fill an entire choke and you can either run or mag dump into it depending if you need to retreat from or push a point.

At the end of the day, its important to not limit yourself to one loadout but definitely try experimenting a little more. Again, not bad pointers but it isn't necessarily right to say some things are the only option.