The development times today are far too long. The technology changes so fast that by the time it flys, it's obsolete. I saw some of the early proposals for digital networks in the space station in the early 80's, that by the time it was launched could have been replaced with stuff from Radio Shack. I don't know what actually ended up in the station, but that effort spent in the 80's was wasted.
If it takes additional money to speed up the development process, then it's money well spent. We developed the entire Apollo system with multiple spacecraft and multiple launchers in less than 10 years.
As for tare weight on air breathing launchers, who cares if it results in a vehicle that can be flown almost daily? Airlines scrimp on weight all the time, changing the number of plastic spoons they carry because some spreadsheet says it will save so much fuel. But they cruise for hours carrying the weight of very heavy landing gear, when they could certainly figure out a way to drop them off and maybe land on water or something. But they don't, because carrying wheels around gives them the practicality of one hour turn arounds. It's worth it.
Tare weight on an air breather, and finding alternatives for very large and very heavy launches, is worth it in the long run.
Oh, and for gaps in the program while developing a REAL space launch vehicle. We should man-rate existing boosters like the Delta II with exact clones of Apollo capsules for a stopgap measure.
For really heavy stuff that can't be broken down into smaller payloads, you just need brute power to climb up out of the gravity well. So big, dumb boosters are probably the way to go there. Figure out a way once they're up there to get them together. I know there was concern in the early days with making that latter step happen reliably and safely, but if we've gained anything over the last going on 50 years in space it is that we can probably hitch things up in an orbital environment.