Technology Bank trades

NP2 trading is fine when you have other players to trade with, but what if you get "shunned? "

What if your team of trading partners is still far behind most of the other leading players ?
Settlers of Catan offers a trading bank for raw goods, perhaps NP2 can offer a tech level bank for active players trailing badly behind. However, trading with the Catan bank often costs more than with other players, so that should reflect on NP2.
A few guidelines, tech levels attained by 80% of remaining players (active or AI) should be available from this tech level bank.
The tech level bank needs to charge more than the standard trade rate.
The bank may electively charge just the standard trade rate for levels 4 or more below the maximum available tech level.

… Example, most players reached weapons 20 or beyond, but the buying player only has weapons 11…
rate for this game is $15/level.
… so buying levels 12 to 16 will be charged the standard $15/level, but
level 17 and beyond, the bank will charge more.