Yeah, the blinking "T" for Shields UP can be easy to miss during gameplay.
Speaking of which, the differences in playfields between Pro and Prem/LE have always intrigued me. It's a pretty fair trade-off, but hard to say which is better if you had to choose. The kickback of the Prem/LE introduces randomness on the playfield(unless you get lucky with a return to Away Team shot) as does the kickout of the scoop on the Pro. Conversely, while the VUK of the Prem/LE returns the ball straight to the flipper, the Rescue of the Pro sends the ball up to the pops for free points. Potentially much more if you happen to have the Prime Directive galactic mode going at the time, as well as a chance at warp ramp shots. It slows the game down vs. the kickback, which may or may not be a good/bad thing.
Personally, I like how the Pro plays. Some of the other features of the Prem/LE are cool, but I think all versions of the game are solid. They really did a good job with that.