The service planners at SEPTA have been very busy bees for this year’s Annual Service Plan revisions, and that work shows in the sheer plethora of adjustments they have proposed, from suburban bus reroutings, to the extension of bus routes to the Delaware River waterfront. But the crown jewel of their work this year is the proposal to chop Route 23 into two parts: a rump Route 23 from Chestnut Street in Center City up to Chestnut Hill, and a new Route 45 from Noble Street in Callowhill down through South Philadelphia. The idea would be for each side to have less exposure to delays, which causes endemic lateness and bunching along the entire line.
SEPTA chose Center City as the place to break the 23 because it had the fewest number of riders going through, as well as some of the worst delays. But to protect the interests of those few riders who do go from South Philadelphia to North Philadelphia, or vice versa, on the 23, SEPTA wants to make transfers between the new 23 and the 45 free.
Already, you might see where this is going wrong. In Greater Center City, the transit network, like the street network, is mostly a grid. This enables people to (again, mostly) predict where transit routes are going, and get between any two points with at most one transfer. The problem with this theory, of course, is the fact that the Center City core is quite a bit wider east-west (and getting wider) than it is tall north-south, our rail transit along Market Street has an express-local discontinuity problem, and a transfer is not included in the base fare except under/adjacent to City Hall, so many high-ridership bus routes like the 17, 33, and 48 run L-shaped to accommodate the primary market demand. SEPTA makes no accommodation elsewhere for riders who might be better-served a more properly gridlike route structure; the free transfer at 11th and 12th Streets would be the first such, and of course it is tied into the ability to do special transfers in software with SEPTA Key.
Someone at 1234 must be grateful, to have been suddenly gifted with the technical ability to avoid a NIMBY pie-fight in South Philly with the relative handful of riders who would be harmed by having their one seat ride broken in two. But in all honesty, it just points out that the entire system is based on an absurd inequity: planning for some people to only pay once (because they have a one seat ride, an unlimited pass, or special deal), while others must pay for a token (or a sucker fare) and a transfer. Not only that, it incentivizes the poorest Philadelphians to engage in pathological rider behavior (prioritizing one seat rides over both speed and comfort) to the benefit of nobody.
So SEPTA needs to stop winking at the right thing and actually embrace it: free transfers across the entire transit system, and a higher base fare to cover the revenue. And it needs to begin planning now, so that it can be ready in 2016 for the triennial fare adjustment.
Sic Transit Philadelphia 
Any back-of-the-envelope about what this higher fare would have to be to maintain the revenue?
And, since you dropped a mention of rail in there, are you including trains as part of the transit system here?
I don’t even want to guess, but since you asked, Sucker Fare $2.75, Key fare $2.00. Somewhere in my archives is probably a breakdown of boardings by fare type, and those numbers could be used to refine the numbers, but I can’t find it now and don’t really think it’s worth a lot of my time trying to find, since Key is going to overturn the apple cart anyway. The real sticky point is weekly and monthly Transpasses, since those are priced to give a discount to somebody who transfers on a daily commute, but not to somebody who only uses tokens.
I was excluding Regional Rail from this discussion; there are worthwhile discussions to be had about RRD fare structure, but those are not this discussion.