I kicked the LBA habit in stages. I've even managed to do something similar with bags, bodies and many "hardly used" accessories. I now have a much slimmer kit!
First was manual focus primes, mainly the Zenitar and Peleng FE's, then all primes covered by the DA 16-45, then all other mid range zooms and my Hartblei Tilt and Shift.
I bought or tried all the mid range primes to see how I felt working with them, these were the DA 14, 21, 40 and 70, FA*24, FA 35, FA 31 and 77. I decided that the IQ gain was not sufficient to warrant the convenience of a really good mid range zoom. I am hoping that the DA 17-70 will perform as well or better than my DA 16-45, otherwise I will start the "hunt the good example" of a DA*16-50.
I'd really like to see Pentax develop a really good DA*15-60 f4.0 with low distortion and cracking optical performance from wide open. That would be an ideal match for the DA*60-250. Nirvana!
I do like macros though, they really are worth the inconvenience because they always deliver the goods. The DA 35 is "very" interesting as it's probably the best IQ from any current Pentax lens. Also, I shall probably hunt for a clean FA 100 f2.8 to partner my FA 50 f2.8 macro in the longer term, although the D-FA 100 is a pretty decent lens and quick-shift is a big plus, but there is something special about the FA 100 macro. An FA*200 macro is an impossible dream!
I've cut down to just 2 zooms (DA 16-45 & Tamron 70-300) and 2 primes (FA 50 macro and FA*300 f4.5) that covered most of the bases. Now sold off the FA*300 in anticipation of the DA*60-250 and will also sell the Tamron 70-300 for a DA 55-300 as it's better and will decide if I will keep it when the 60-250 eventually arrives, as it's small enough as a travel zoom to partner the 16-45 or it's replacement. I've often thought about the 12-24 after being very impressed with a sample I had for a while after dissapointment with a couple of Sigma 10-20's, but I rarely miss or need the extra width, I eventually sold my Zenitar because I always reverted to my 16-45 even though I had to either step back or preferably do a 2+ image stitch.
If the DA*60-250 doesn't deliver the expected performance (I hope it is in the same league as the 50-135), then I may well opt for the DA*300 f4.0 and just live with the 55-300 for the mid-long range zoom convenience.
So that's it for me, a macro or two, because they are the ultimate in IQ, and a couple of the best overall zooms plus maybe the best long prime, currently the DA*300, and a decent TC for it or the 60-250.
Collection is definitely not for me, I'm much happier now I don't have to agonise over which lenses to take/use every time I go out, plus I have a much more transportable kit. It has actually made me examine all my aquisition/collecting habits and I must admit I'm much happier!