I think the sidearms add an interesting layer to loadout choices for people who don't run a large firearm and load up on perks. Whether that strategy is worth it after the Collector nerf is debatable.
In my opinion the beginning of the game is perhaps the most important time in the match, and players who run large firearms are more likely to cash in on early kills. This results in more parts to go ahead and improve their combat efficiency. Players running sidearms have to utilize crafting and healing to keep pace, but often times this isn't worth it.
I still think the sidearms keep this game feeling like TLOU. If they were taken out it would undoubtedly start to feel more like COD. Which it is already starting to with the SAR abuse.
I think that the game would lose a lot of its appeal and balance without sidearms. Not only are they fun to use, but they offer a great complement to main weapons. Of course, for someone who mainly uses SAR, sidearms are not that important given that the SAR does pretty well on all ranges. I for one like to experiment with other weapons and use HR a lot so I like to combine HR with the revolver to cover mid to close range and compensate for the HR's low fire rate. When I use the bow I combine it with shorty to compensate for the bow's lack of stopping power and when using the burst rigle I like to combine it with 9 mm because both are great with SS3 and work wonders on CQC maps.
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