Of course, it will hurt build diversity to some extent but since I don't have the product in hand, I'm willing to give the benefit of the doubt that HBS won't screw it up too bad and create a One True (and probably not stock) Build situation in the mech lab.
Most of the fixed equipment seems to be in the CT or head. Not all but a lot.
Rifleman has further sensor(sight?) range and decreased recoil penalties due to a built-in head equipment. Which unfortunately limits using any of the cockpit mods. I think there's at least 1-2 others in the same situation.
Archer was one of the few that its equipment in a side torso; has improved LRM clusters and higher stability damage for SRMs and only takes up 1 critical.
I forget specific examples but a few others reportedly have their equipment in the CT, which unfortunately would remove the ability to add better gyros (I really like the + hit defense gyros).
None of the objects are big and none take up any additional weight. I would definitely prefer if they were just part of the chassis in a way that didn't take away other critical spaces or at least were like the Archer's and out of the way. Since a lot of equipment is already smaller than in TT, losing 1 crit isn't as big of a deal but I found the gyros and cockpit mods make a pretty big difference (like not having a pilot out for 2 weeks due to an unlucky missile hit).