OK. Having actually tried it out a bit in various actual gameplay scenarios, I am now prepared to offer my feedback on the Personal Force Field change. And while my impression of it has improved upon use, and while it's very close, I still think this is not the version of PFF that I ultimately want. I actually really like being able to turn PFF on in the middle of things without having to effectively remove myself from the fight, especially with all the new tools Force Field has gotten. Given the new role of the set with this redesign, that is not a factor I would be willing to give up; I definitely prefer "shoot through PFF" to the old PFF, even if it is much more limited in duration. However, I dislike the mechanism which disallows the player from simply staying in PFF all the time — a hard 30 second time limit on the toggle itself. The reason I dislike this is that there are no visual indicators for when the toggle is going to drop — you simply start taking a lot more damage if you still have aggro. For Masterminds this isn't a tremendous concern because they are likely not going to be holding much aggro themselves, but for the other ATs, and Controllers in particular (who naturally draw a lot of aggro because enemies hate Mez), I think this is a significant issue, *especially* because the set's redesign encourages Force Bolt/Repulsion Bomb spam and increases their damage output for the two Force Field ATs most likely to draw aggro.
Personally speaking, I would vastly prefer for PFF to simply be the heaviest toggle in the game coupled with that 90 second (or maybe 120 second, if need be) recharge. I'm talking upwards of 4 END/sec. That puts a pretty strict limit on how long you can maintain it in the middle of a bad situation and still contribute to the team, but the player has multiple tools to manage and/or extend that duration themselves, and you have a very obvious visual cue for when it's about to crash on you (and have reason to cancel it early yourself). This makes PFF a big power with a big impact, but difficult to master and very demanding of investment if you want it to be truly powerful. It also has the side-effect of allowing players to use it very similarly to how it functioned before if desired simply by slotting it for END redux and making sure you have Stamina slotted. (It also happens to justify the power's appearance later in the set for Masterminds thanks to their built-in Endurance penalty.)
I do recognize that there are several END management tools that run the risk of making "shoot-through" PFF whose drawback is a high endurance cost a ridiculously powerful power. I am personally of the opinion that this is not more game-breaking than building for a large amount of Defense from IOs, but I also acknowledge that it's a legitimate balance concern that needs careful consideration. If the team believes this is not tenable with the prevelance of +END IOs/Speed Boost/Ageless Invocation, then I would at least request that the team consider converting the power to a click so that the icon under your Health/Endurance bars blinks as it is about to expire. This is more difficult to notice than the blue bar crashing, but at least it is a visual warning of some kind.