Yes, implementation of any such system would be a headache to develop. With some thought, it might turn out well though.
One possibility is to create sort of a server capship registry, a voluntary thread where anyone who wants to apply for the "Expensive Ship Grant" can post information and the rp of their ship and crew (or provide links to it in a separate story thread if this is their thing).
A fairly rigid set of criteria would have to be used to evaluate each entry. Sort of a template really breaking down what calibre of post would achieve a certain level of credit. Each post is evaluated with this, and then the player is granted a certain amount of money towards the new ship based on the criteria and ship value. Finally, limit these grants to a certain number per player per time frame. Something fairly harsh like 1 every 3 months or so.
The idea here then is that people should not be submitting requests all the time, nor if they already have a billion dollar bank roll.
Main Problems:
Somebody taking the money and using it for completely different things. Might be hard to detect as well.
Who will do the work to parse the thread and give the handouts? This as always, is the big one.
So, more suggestions might be good. How can this actually work?