"Although a half century old, most of the internal fear has been replaced with modern electronics and furnishings." should read " Although a half century old, most of the internal gear has been replaced with modern electronics and furnishings."  The internal fear part should be mostly limited to being in a plane that is 50+ years old and filled with explosives. Wikipedia says that "Production ended in 1962". 

The B52 has certainly gained the reputation of being the greatest strategic bomber ever built.  I have wondered if it would be practical to build new ones, but I suspect that it would be more likely that the next low-cost / low-mission-intensity heavy bombers will come in the form of up-sized unmanned drones flying alone or in clusters, rather than as a single, high flying, high-speed jet bomber.  It is important to not confuse the B52s longevity with its effectiveness as a front-line weapon.  Its size, heat signature and radar cross-section makes it vulnerable to modern air-defenses, regardless of the rosy proclamations in this article.  I don't believe that an enemy has fired on a B52 in anger since the Viet Nam war, and none were brought down by enemy action since that time either.  (The lone B52 lost in the Gulf war was brought down by a technical glitch.)  Without complete mastery of the air or a technologically backward enemy to bomb, the B52 would be a sitting duck.  But our conflicts since Viet Nam have been against third-world powers with third-world air defense capabilities, coupled with a strategy designed to methodically peel away the thin veneer of modern anti-air capability before we send the BUFFs into combat.  In short, the value of the B52 is the same as that of a freight train:  it's cheap to operate and economical when taking into consideration the amount of fuel used to deliver each ton of ordinance.  No more... no less... In time, that value will be overtaken by a future generation of unmanned drone aircraft.

Until they literally fall apart from wear and tear, the B-52 will continue to be a dependable aircraft, provided that the appropriate upgrades are regularly made.  I just hope that none of them will be sold/given to unfriendly or overly-ambitious countries.

"The basic airframe should be large and flexible enough to be used for functions such as AWACs, ELINT, EW, ground surveillance radar, maritime patrol, tanker, etc. as well as being a bomber. And by this I mean that the basic design could be adapted to these functions, not that each could do everything." 

Honestly, the simple 'bomb truck' role could probably go almost as simply to a 757 or 787, and enjoy mass production discounts, the widespread availability of common parts, and easy familiarity for commercial pilots (if it's ever required).