I don't think the more casual players such as me would want to spend months to RP in forum just to get a standard capital ship. I am not very interested in maintaining a POB (with the constant resupplying and stuff) to just to obtain a capital ship either. POB already has its own perks such as unique equipment and business opportunity to justify their cost and dedication needed. A capital ship in this mod isn't really that overpowered or so special compared with other ships to justify forced in-forum RP or POB building in my opinion.
I think there is a misunderstanding here, writing an essay and roleplaying are two different things that do not have so much in common. Roleplaying means interacting with other characters according the character parameters (psychology, history, goals, etc). The story creation is the results of these interactions, it can be written by the roleplay participants but it's not a requirement. Roleplaying is something fun, not limited to PvP, trade and mining. It's about playing a role, not writing a story.