Changing the subject a bit, TRAINS Magazine (a national magazine covering all types of railroad news across North America circulating to nearly 100,000 subscribers) is doing a cover story on FrontRunner this month:

The story describes how UTA got to be in the unique situation of running all the transit along the Wasatch Front, rather than having separate agencies do light rail, bus, street car, and commuter rail. That alone gives UTA an amazing advantage compared to other transit agencies. It also describes how UTA got its own separate right-of-way for FrontRunner, which is also extremely unique. It made me remember how awesome our rail transit landscape is compared to every other metro area our size, and also compared to many other cities much larger (such as Seattle, Phoenix, Huston, etc). So while I often complain and promote ideas to make FrontRunner better, it is because it is so awesome already and has so much built-in potential to be truly amazing.
The story ended by described some of the future plans UTA has for FrontRunner, and it was all the stuff we heard about before... Extensions to Payson first, then Brigham City, then perhaps all the way down to Nephi. Double Tracking was mentioned as a high priority despite the expense, but electrifying wasn't mentioned (ideally you'd want to electrify after all your track is in its final location, so that you aren't moving catenary foundation poles in order to fit a second track into your alignment). The most immediate project mentioned, though, was added a second commet car to every consist, which would require both repairs to the currently out-of-service commet cars sitting at Warm Springs, and also lengthening platforms and crosswalks at practically every station.
Currently, only 5 of 16 stations can handle a second commet car on every train; Salt Lake Central, North Temple, Layton, Roy, and Ogden. That means the other 11 stations will need significant modification before these longer trains run. Take Provo, for instance. Because of the grade crossing immediately north (railroad north, actually west) of the platform, the second commet car would have to be positioned at the 'high block' area, where the platform is raised to the Bombardier floor height - 25 inches above the Top Of Rail. The lower step of the commet car is only 18 inches above the TOR, meaning there would be a 7-inch step
down to the first step before climbing up into the car. The only way to solve this problem would be to grind down the platform to a more appropriate height. And that sounds expensive to me. I wonder if UTA can somehow get a safety waver from the FTA/FRA that would allow them to operate with a step down before up?
It will be interesting to see how UTA solves this problem that it was not designed for. Each of the south stations (and North Temple also) has room for a 4th Bombardier car, but none of the others do. It's kind of crazy that UTA didn't construct is platforms in the South section with enough room to run a second commet car, because they did construct them that way in the North section. UTA knew it had enough cars to run a second car in each train and still have extras, but still chose not to design their platforms with that kind of capability (they have 25 commet cars total, 18 would be needed at peak hours with 4 more on the standby trains). They also knew that their yard areas aren't big enough to handle the longer trains. Perhaps they will finally construct long enough yard tracks in the old Salt Lake container yard.
Long story short, UTA knows they need to add capacity, but there is no easy way to do it. They've maxed out their options, so they've got to work on several fronts that will all require modifications/construction. Adding cars will require platform changes and yard capacity, while adding a second track will take time and be expensive.