I agree with a lot of what has been said, but have some questions...
Why would you want to run K-cars on the 56? I think it'd make a lot more sense to completely upgrade the 56 to the standards of the Subway Surface lines currently being rebuilt and then buy new low floor trams for the 15, 23 and 56. The surface trolley routes require little if any capitol expenditure to be made ADA compatible outside the new cars. The Subway Surface stations OTOH must have W/C Ramps or elevators installed to become ADA compatible. In the near future SEPTA only plans on making 13th and 15th ADA compatible, that still leaves most of the system non-compatible. UPenn might help offset the cost of making 36th-Sansom ADA compatible, but Drexel won't do jack-squat about 33rd, the geometry of 37th is awkward, and 19th and 22nd are low probability as well. Instead run the low floor LRVs on the 15, 23 and 56, then at the end of that order, get 120 more for the Subway Surface routes. In the interim between the purchase of the Low Floors and the retiring of the K-cars, the PCC IIs that were to ply the 15 can be upgraded to be CBTC compatible and run as ADA compliant trolleys on the Subway Surface lines.
Also why would the 23 and 15 be cheaper to bring into service than the Trackless Trolleys? The wires are almost all there, probably less than 1 mile of wire is actually damaged in the whole system and it's perfectly serviceable. SEPTA could get in on the E40LF order Vancouver has placed, perhaps even getting the same Kiepe IGBTs and such the PCC II fleet uses, so as to maintain some mechanical compatibility or at least reduce parts counts. IMHO the 23 is pretty gone in spots, and downtown's operations need to be rethought, perhaps including signal preemption, or making 12th a transit mall from Noble to Bainbridge with both north and southbound 23s on it, but there's a fat chance of that.
Why must the R3 go to West Chester? Why not extend outward to a growing area? Why not go to Kennett Square? Rebuild the bridge at Wawa, and perhaps have a branch off to West Chester, but the main traffic would go to Kennett Square, or perhaps Oxford. Didn't SEPTA close the R3 West Chester because they felt it was close enough for people to drive to Exton and such to catch a train to the city? It's clear that Kennett Square and places like Chadds Ford are much too far from the railheads and need better access to rail, which sending a rail line north to West Chester will not solve. Perhaps SEPTA's regional rail plans would be best served if they were more for filling in gaps missing from the radial layout than having lines head toward one another or extending outward. Lets serve more of Bucks, Montgomery, Philadelphia, Chester and Delaware Counties before we go giving service to Berks and Lancaster counties (it hasn't come up yet, but the R5 to Lancaster must be on Somebody's head). This would mean that the R8 Newtown is out, it's a duplication of the R3 West Trenton, the SVM to Reading is out, let BARTA build their own goddamn train, not saddle SEPTA with it, the R3 West Chester is out, it stops 5 miles short of the R5, Kennett Square is 10 miles from Thorndale, and 10 miles from Wilmington.
It may seem mundane, but IMHO the three biggest items on Mr. Mitchell's list were the 3 entries at the bottom, 14, 15, and 16. SEPTA needs to switch to a modern read-write farecard good on all services, they need to have a Busview-like system for getting information to passengers on the status of their trains, subways, trolleys and buses, and they need to run later and more often. All three of these are relatively cheap prospects that could have the effect of greatly increasing ridership by making transit easier to use. It'd be nice to have a card similar to NYCTA with 10 dollars stored on it in my wallet for use in emergencies. If SEPTA can manage true connectivity with the system and give RRD C/Rs a reader/debiting machine for the cards then we can maintain the great system wherein a monthly pass for regional rail works on the buses, and vice versa. It'd be great if I could check SEPTA's site and learn the R5 train has a 10 minute delay due to an amtrak train stuck on the main line, I'd know not to run for it, and instead could be planning ahead.
As for Busview, I only know of one city that uses it, Seattle's KC Metro, it's a Java Applet that shows the real-time position of nearly every bus out on a route, as well as giving ETAs, alerts when the bus reaches a certain point, and describing what bus is where. As railfans imagine the boon it would be to check SEPTA's TransitView and find out that 2308 was on the R3 today, or that 2329 is making a trip on the 13. Of course there might be productivity losses at some offices (I know mine might suffer), but I think all in all it'd be a good thin in the end.
http://busview.org/busview_launch.jsp
Do note that this link will launch Busview's applet as well as it's homepage.