Hey Spooky39,
You are not required at all to re-grind a line if you don't want to but you would if you want to use the NTC. This will be optional and only if you want to take advantage of some of the unique content that you can get, but by no means is it mandatory. There will not be any direct performance buffs in the NTC, so it will be up to you if you want to do the grind again for the resource that the NTC will provide.
Right now the NTC is still in a significant redesign and the Ohio and Colbert still in testing (albeit publicly) so it's a little early to make concrete statements on how these will look when they go live. As you know ships can stay in testing for awhile and go through numerous iterations before release. As we get closer to the release of this system and it's rewards we'll certainly release more information about them.
As we've stated previously it is never our goal to release an imbalanced ship because it's just not overall good for the game.
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