The solution is simple: make the higher order jump drives even more
expensive and space consuming. Or, change it from the M-Drive doing
the pushing to a secondary part of the jump drive, allowing a matrix
of Order^Exponent. So a 1^1 is the cheapest, while a 6^6 is the most
expensive one possible, and has the highest minimum tonnage
requirements (say, 100,000 tons).
We still won't hit Andromeda though, even with the 6^6 drive making it
only 18 jumps away - Jump 2 or 3 is the maximum that allows deep space
fuel depots that don't require a local hydrogen source (any higher
jumps require 100% or more of the ship's tonnage to carry two jumps
and a decent fuel load, unless you have huge J4 fuel freighters).

On 8/4/17, C. Berry <xxxxxx@gmail.com> wrote:
> The trouble with a galaxy-spanning game is that there are hundreds of
> billions of stars in our galaxy. Unless the campaign totally railroads the
> characters, there's no way for the GM to be ready for all the places
> characters might go. Traveller narrows the choices enough that you can
> flesh out a dozen worlds and support a long campaign.
>
>
> On Aug 4, 2017 10:47, "Timothy Collinson" <xxxxxx@port.ac.uk>
> wrote:
>
>> Oooh. I do rather like idea of a setting where a galaxy is accessible a
>> la
>> Asimov's Foundation.
>>
>> Or Lensman... I really out to tackle them again.  No recollection of a
>> schoolboy reading.
>>
>> tc
>>
>>