It feels that you have rushed this game to the point of release when it is no where near ready for retail release, in my job I deal with software releases, upgrades and software patches every month we perform UAT extensively and if I allowed a system to be released in this state I would be looking at possible dismissal as the impact is extensive, low framerates on high end machines is just not acceptable, there are so many things wrong with this game I don't have the time to log them all. Please give the community some assurance that all of the issues raised by users are addressed for the next Beta release the users in this community have paid you money for a product that currently isn't fit for purpose. This is a game that many users have been waiting for as a tactical shooter if it isn't ready at least delay the release until all issues are resolved and you can gain the confidence of the community once more.
This game is still really solid despite the poor framerates in the beta. On the second day of the beta they increased the framerate significantly, like 20 frames, with the August 10 patch. If they can improve the performance by that much in just one day, I'm pretty sure they will have this thing running smooth by the next beta and even better at launch. Have faith.
This is a beta. Beta means it's not meant to run like it will in months to come. It's an early access to the game that is still under development. Any game's beta is going to have performance issues, bugs, etc etc. That's just part of betas.