Mmm, while I like the idea of base-access Wereworths, conversion to prestige wouldn't work, because it'd be easy to cheaply convert influence into prestige.
not if it used the same conversion ratio as the SG registrar 
not to mention the fact that the BM/WW take their cut out of the profits as well.
prestige earned could be "pooled" like the tickets in MA that you earn for people rating your missions and then the SG permissions could decide who has the right to collect the pooled prestige. this would help with managing the bits after the decimal point....
It would also allow group members to make more of a contribution. By this i mean, those alts that cant solo very well and/or find it hard to find a team. instead of completing missions and beating up bad guys htey can earn SG prestige by supplyign the heroes (or villains) of the world with devices and resources to help them in their objectives....
not a hugely massive idea but just something I'd like to see:
in a tech base: a huge wallscreen that acts as a connection to the black market or wentworths. From here you can buy or sell items BUT all inf earned is converted into prestige for the base and goes directly into the SG coffers (at a ratio of 1000 to 1 or whatever it is with anything less than .1 of a prestige poitn being discarded).
in a magic base.. ehhhh a large crystal or a bowl with smoke rising from it that displays the data...
as I say its not a huge idea, but it would encourage SG members to sell gear for the benefit of hteir group without having to sell at BM/WW, go back to collect inf from nearest BM/WW , travel to city hall / arachnos tower , talk to the SG registrar and then convert a large chunk of inf to prestige.
One side benefit I would see is items being sold on the market which pull inf out circulation.
Another additional benefit would be allowing SGs to sell IO recipies (ok , they cant be stored and stockpiled but a player could sell them directly from their own inventory).