Recs.
Updated
Tactical Realism mod for Operator. Many dramatic changes for a vastly improved tactical experience, and immensely improved tactical realism. Be warned this is very different from vanilla Insurgency, and there is a rather large learning curve. But the community is friendly an eager to help, and if you take the time to understand it, the gameplay is very rewarding.
Steam Guide:
https://steamcommunity.com/sharedfiles/filedetails/?id=1639461466
ModDB:
https://www.moddb.com/mods/operator
Specs
Pros
Pro One of the very few games with more realistic accuracy
So many games that tout "realism" as a feature completely miss one of the most important factors of tactical realism: accuracy (or rather inaccuracy). So many games give you laser accurate weapons, where even with pistols it's rather easy to get a 100m hit, on the head, standing, right after a sprint. Operator models far more realism in it's sway model, but at the cost of feeling very foreign (especially given that, realistically, most of such sway will be in sight misalignment, and Insurgency does not model that). Still, it's one of the most comprehensive attempts out there.
Cons
Con Still has some of the realism limitations that Insurgency does
Being an Insurgency mod, there is only so far that Operator can practically push the realism. It is a massive improvement over Insurgency's attempt at realism, but there are certainly holes in the paradigm stemming from limitations in INS (eg: bullets are hitscan).
Con High learning curve
If you know a lot about tactical realism (how armors actually perform, calibers, tactical wisdom IRL) then the curve is much less steep, but for most players of tactical shooters, this much realism will be jarring, and will certainly take getting used to. But the gameplay is very good, and reading tha manual should be enough to jump in and do some damage. The game is encourages skill, and although non of the system dynamics are patterned/learned [eg CSGO recoil pattern], they do take high general mouse skills (controlling the random sway and recoil) to be exceptional. Tactics trump skill most times in Operator though.