The real key is to design the design system before releasing a bunch of hand-waved stuff that ignores the design rules.
I will go on record right now, that I would happily buy every book for Mongoose Traveller 3e IF it was just all of 2e, but with Sigtrygg's "All the background assumptions & design rules in one boring book that only grognards buy" as a foundation. I am a grognard, and I will buy it. It might be super boring to create such a 3e Bible, but it keeps discrepancies and weird exploits from creeping in and making life miserable for the Game Masters. The 'just hand wave it' crowd insists that discrepancies will come out of providing 3e Biblical-style details -- but with so much crap already hand-waved, how can you possibly claim that there are not already discrepancies? If the answer is 'Well, sure there are some -- but GM fiat can just cover that' -- then wouldn't that work equally well with a 3e Bible of build systems? Wouldn't you expect that things built consistently with the same pre-thought design sequence might be in less need of GM fiat?
Go ahead and finish 2e; write books for all types of new adventuring styles -- maybe there needs to special rules for wandering David Carradine style martial-artists who fight evil. Maybe there needs to be a book about how to have adventures with founding and running an underground Psionic Institute. Maybe someone will finally get around to answering 'Why is there trade between Sectors and Empires?' by writing a 'Sector Builders Handbook' -- complete with what kinds of market forces drive long-distance trade up and down the Spinward Main. Maybe there is a burning need to detail the kinds of cultural priorities motivate the Third Imperium & various Foreign Empires -- how do Aslan classify worlds & prioritize them for conquest? What about the Vargr point of view? Are the K'kree interested in any worlds which are not open savannah? What the hell are the Hivers really after? What do the star-charts for each of these empires look like, and why? What values do they include in their UWPs? How they think and behave shapes what they want, what they trade for, what goals they set, and why they go to war -- write that book for 2e, complete with all the glorious nonsense of 'we just handwaved this without reading anything else we have ever published -- but it works in this book'. Go ahead and create 'industrial production' rules that are use credits in some places, dTons in others, Resource Units in others, kilograms in others, and People-Work-Hours in yet other places, none of which works together; get all that stuff published & out there. Mass combat. Converting the heathens. Exploration. Piracy. Science. Colonization. Extinction. Deep history. Everything.
Then sit down to do 3e correctly; and start with the Bible of build-rules.
Once everything is written, make the effort to actually make it a coherent whole -- where TL makes a consistent difference from 0 to 35 (or 0 to 100, or whatever, as long as it is consistent throughout), where the units are all the same and scale correctly. Don't rush to a deadline with the Bible, but do it first.
I will buy it. I will buy all of it.
