Thile: I think that they have some duplicates in there, under different headings too, as I recall.
I think it just needs a good seeing to, with maybe the the more outrageous weaponry pushed to the back of the book where you don't need to go through it to get to the more used stuff, but also, perhaps, treated a bit like an encyclopedia with tabs on the outside of the pages to help you find the sections more easily, so you can see the darker print of the tab when the pages are closed - that would allow you to find the section you need quickly - useful in such a large book.
I think that, also, rather than having weights, sizes and prices for everything in their descriptions, having them in a table, much like the weapons, would be a great help - especially if permission was given to photocopy those tables for personal use (I believe a small amount of each book is allowed anyhow)... you'd only be pulling the book out for looking up unusual items or for descriptions... the rest of the time you could use the photocopied page in a smaller report file.
I know I'd be compiling "Character Creation Booklets" - comprising the basic character creation pages, the tables for the most commonly-used equipment and the most available subsector listing for the area you're playing in, to prevent books being passed around excessively during character creation... they'd then need the career book for the class and they'd be set. I'd also be tempted to put the Scholar and Citizen careers from the MRB in there too, since they don't exist outside of it. I also have a pair of the "Introduction to Traveller" books if players need more information, but the CCBs I like to keep "lean and mean" for players who know what they're doing, but need information to hand.
I would also like to see the CSC include all the specialist equipment from the career books to date too (and possibly a couple that were in the works, if possible) - they're starting to suffer from fragmentation a bit - a little like another publisher's series with a whole load of World Books and Dimension Books (you know the one I mean), but less so. Keeping the various bits and modifications together might help when trying to remember which damned book you saw it in.
Also, another thought occurs - how about Rulebook Light - the Introduction to Traveller (Book 0) booklet which contains a very light version of the rules, including character creation - I'd like to see that rewritten so, instead of Army and Navy, you have the Citizen and Merchant classes in there - the two most common, as well as a good write up on the Air/Raft and maybe a deckplan (maybe a Type-S) to get players started. The ItT (Book 0) booklet has huge potential and I think it might just be a good one to rewrite and draw in new players. If you can play it on its own, but with severe limits on what you have available, then you have a base to make players and GMs alike to want to buy more books. But the main rulebook DOES suffer now from a large degree of redunancy. The ship construction rules are enhanced elsewhere (and used once in a blue moon and then only really by the GMs), the alien creation rules are elsewhere, the equipment is a very condensed version of the CSC (and a few guys I've spoken to have said that most players make a beeline for the career or CSC books for equipment anyhow, or just use the very basic stuff that's available in the book. Psionics and Trade have their own books now.
I think a cheap alternative to the MRB is a good thing to maintain, since it allows more players to own their own books (and, let's face it, the Book 0s are quite handy when people need to reroll characters since practically the whole section is in there, aside from the careers, which are mainly in their own books now anyhow) without any of the Ref's information, which is pretty much useless for anyone who never intends to be a Referee... Maybe a rewrite of this book may be a good idea (if it's cheap enough, maybe releasing it for Free RPG Day too...). There is currently no LBB version of the book too, which may be useful to bring out. It would also be useful for those old-school Refs who don't like players having all the tables and information to hand... or those players who like to use other people's books at a session and like to travel light (we all have them - the players who end up everyone else's books, often including the rulebooks, but also including pencils, paper and dice, all too often... at least a cheaper MRB we could *possibly* get them to pay out for... or have a whip-around and buy for them...)