I posted this over on the Insurgency reddit, and someone suggested posting it here for the devs to see. Hopefully this is useful. Copied below:

I've played a few hours of the beta now, and I wanted to constructively raise a few issues that I haven't seen getting much attention, make a few suggestions, and offer some observations about the complaints I've been seeing. A lot of people have observed that the game now feels like Battlefield, which I can understand, but is also somewhat surprising as a lot of things haven't changed that dramatically from Insurgency.

I hope this is helpful.

Movement speed is way too fast. The sprinting speed in particular is incredibly fast, and the effect is something like playing Battlefield with Insurgency's somewhat realistic gunplay. I realize Insurgency already had rather unrealistic sprinting, but this feels faster. If anything, things should've been somewhat slowed down. Insurgency's never been a simulation and I realize that isn't the goal, but movement this fast has very significant effects elsewhere in gameplay: cover and positioning matter much less because there's very little cost to being recklessly exposed or taking a corner sloppily. Reaction times can beat situational awareness and positioning, which is pretty much the core of the Battlefield/COD experience. The mobility difference between a heavy loadout and a light loadout in Insurgency was never really significant, but Sandstorm has me wondering if it's even modeled anymore at all.

I've also been a little surprised at how many shots it takes to down an enemy, but I suspect that the movement speed contributes to missing shots more than you might expect. I don't know how the team is modeling armor, but based on comments I've seen elsewhere, the devs seem to understand that hard armor plates basically stop almost all of the weapons in the game currently. They were definitely right to remove AP rounds, not just because there was no reason to ever not take them, but because they were actually extremely unrealistic. I don't want to comment more without knowing more about how they're modeling armor and damage, but a headshot still kills instantly with just about any gun, and I'm not sure things would feel as wrong if the movement speed were toned down.

Recoil is too low in full auto when aiming. Right now, with and M4 or G36 or AK74 (for example), it's very easy to keep every round directly on target in full auto out to 50m. This is definitely too easy. Recoil doesn't need to be extreme, but it's low right now. This is also contributing to the COD-like feel.

Rifle fire selectors should be set to semi auto by default. This would make sense if full auto were harder to control.

Red dot optic bodies and rear iron sights should be blurry. In reality, with both eyes open, CQB optics like a red dot largely blur out of view. I've never seen an FPS attempt to render this, but given how faithfully the game tries to recreate the effect of magnified optics, this feels like an odd thing to leave out now that the game is running in UE4. And with modern optics getting smaller (like the Aimpoint Micro or Comp M5), this sort of thing actually matters, because modern smaller optics are a significant disadvantage when they really shouldn't be.

2x magnifiers can't be flipped out of the way. The main advantage of flip to side or detachable magnifiers behind an Aimpoint or Eotech is that you can switch depending on what you're doing. Even Modern Warfare 2 had this in 2009.

Eotech reticle is too thick and bright. it just needs to be toned down. These things are adjustable in real life, and it shouldn't be so overpowering that you can't see what you're aiming at.

IR lasers would be nice (if night is coming back). I don't know if Sandstorm is going to have night maps, but the coop survival at night was one of the most memorable modes in Insurgency. Night was actually dark, and you needed a flashlight or NODs to be able to fight. It actually felt like coop survival horror, which, given the setting, was quite unique. In reality, visible lasers are basically useless and nobody uses them, but IR lasers (which are invisible to the naked eye) and IR illuminators are the main way of seeing and shooting under night vision.

What happened to flashlights? Most of the maps I've played so far have incredibly dim lighting and it feels like they've crushed the blacks to get a more dramatic visual feel, but it's very hard to see. Flashlights are much more useful than lasers in reality, and with the extremely dim lighting, this is only more true ingame.

Red dots on pistols would be good to see. This is where things are headed now with real handguns. It's not critical, and the handguns in game are just fine, it would just be a good addition. I was also pleasantly surprised to see compensators on handguns as an option, as this has been niche trendy for the last year or two, though in reality they look like this.

Extended magazines are very weirdly implemented. They seem to add something like a flat 10% to magazine capacity with no visual change, which isn't useful and contributes to the arcade shooter feeling. It's also an odd choice when real larger capacity magazines already exist and would interestingly change up gameplay: 60 round Magpul drums exist for the AR, 60 round quad stack magazines exist for the AK, the M249 takes both 100 round sacks and 200 round boxes, 21 round magazines exist for the Glock 17, etc.

Reloading is too fast when retaining magazines. The speed is fine for dropping magazines (some of the pistols feel a little slow, if anything), but the reload times for retaining magazines are a little too fast and are one of the less significant contributors to the COD-like feel. More importantly, differentiating retention and speed reloads would make the decision more meaningful without removing the ability to respond quickly under fire.

The Hi-Power is too small. It's an easy fix, the model just needs to be scaled up slightly to be the right size.

Remove long barrel and flash hider options. In most cases, barrel length is what weapons get designed and built around. It's not a modular feature you can just change. Flash hiders are basically the default muzzle device that's on nearly everything in the game already (and they do not completely hide muzzle flash, they just reduce visual signature). I don't think it's impacting much at the moment, but the easiest solution is just to remove the options (and make compensator the default option for guns that have something like a comp already on it like the AK74).

Extend the arming distance of the 40mm grenades. They're usable in CQB right now. In reality, these things need to travel at least 15m to spin and arm. 15m would at least stop them from being used indoors while still accommodating Sandstorm's very close engagement distances.