Do not have to many regrets of getting rid of any of my past cameras, mainly because I have held on too most of the ones that I liked using or meant something to me.
Still have my first camera a Kodak Brownie, picked up a copy of my first serious camera a Minolta HiMatic 7s a few years ago in Japan, still have my first Nikon F body, bought a second F last year but have dumped all of my other F2s, F3s, F4s, Canon EOSs, Hasselblad 500CMs, Bronicas, Sinar P 4X5 Contax 645s, Contax G1, Canon 1Ds Mk IIs, all but 1 of the Canon 1Ds Mk IIIs, all of the Canon 1D MKIVs, Olympus EP1&2, Panasonic GF1, the Leica Dlux III but still have a IV, all of the other p&S cameras from Canon, Nikon and Sony are gone.
Still have all of the Ricoh GRD I, II, III, IV cameras, the Mamiya RZ, the Fuji 680, Toyo 4X5 and 8X10, Contax G2, Contax TVS I and II, Minox 35, Nikon SP, Canon 1DX, Leaf AFI Hasselblad H2 and H4, Olympus OMD, Fuji X10, X100, XPro1, plus my long list of vintage miniature (16 mm and Minox), 110, 35 rangefinder, Polaroid, roll and cut film cameras.
As to the original OPs topic there is nothing on the market in hand hold able cameras than can compete with the versatility of the FF DSLRs, but honestly that need for me only applies for work, when shooting for myself much prefer shooting with the XPro1 and or OMD. For example yesterday shooting a small job for me shot about 3500 frames with a Canon 1Dx and 850 with the Leaf AFI, neither the OMD or Fuji could have kept up, but on the other hand I had 5 assistants, 3 tripods and a 35ft truck for all of the equipment not something I even want to think about when shooting for myself.