you're far from the first person to make these observations. They seem to recur on the various Tekumel lists and forums once or twice a year. As usual, they seem to assume that there's some company or organization out there looking to revive Tekumel. If you've got the money to invest in a new version of the game, seize the day. Otherwise consider that there isn't anybody out there listening who has the means and interest to use your unsolicited recommendations.
Barker's heirs have formed a non-profit foundation to manage the intellectual property and handle copyrights and licensing. The Tekumel Foundation ( ) is not a business, they don't have the intention, capital or the expertise to produce new games. It took a lot of their limited resources just to employ an intellectual property lawyer to resolve the mess of old contracts that Dr. Barker left behind. Now they seem to be struggling just to manage the enormous archive of Tekumel material the Professor left and get a few pdfs distributed.
Tekumel has had more than it's share of bad luck along with bad business decisions. The most recent game system (Tekumel: Empire of the Petal Throne) was written by fans, who then contracted with an active game publisher, Guardians of Order, to do layout, art, publishing and distribution. Unbeknownst to the writers, GoO was in dire financial shape. They published the gamebook, but without incorporating final edits, and then went out of business within months.
The version before that, Gardasiyal, was fully published, but with a poorly conceived pricing structure, and it had no commercial success.
Before that was Swords & Glory, intended to be in three volumes. The first one, the Tekumel Handbook, had a good print run, the second, the Player's Handbook, had a brief run, the 3rd, the GM's guide, never made it into print. I'm told part of the problem was the loss of an enormous stock of printed volumes to flooding.
There is some good news though. There is a new set of Tekumel rules in the works. The game is called Béthorm, it's been written by Jeff Dee. He's been doing a series of Kickstarters to fund the project, first artwork then he'll do one for the game itself. He's playtesting now, maybe if you contact him you can get in on that...
http://bethorm.com/