For those people who do still fly caps regularly, the difference will be felt hardest. There's no telling what implications could arise from making them slower. Navigating asteroid fields from what I understand takes long enough as it is. While your model proposal is admirable in theory, I cannot see how one can justify giving a capship a means to dodge anything. By their nature they are built so large so as to take a battering while unloading salvo after salvo of ordnance at the enemy.
Gunboats on the other hand are designed to be more maneuverable and would therefore adhere better to your proposal.
My issue is: Put yourself in the shoes of a brand new player. Not a few weeks into discovery - very complex lore to understand and adhere to so as not to step on any toes. You've saved up enough money for a capship to show off your prowess as a player and to explore a new style of flying. Little beknown to you the ship takes ages to get anywhere and when a fight does arise all you know about how to win a fight is absolutely useless. You quit.
What your proposing only accommodates one style of fighting in a capship. I've seen an outcast BSs charge head on into colonial ranks attracting enemy fire while the rest of the fleet sits by and mortars the lot of them. Jump drives are used by most militarised official factions now and play a key role in flanking attacks.
All i'm trying to say is while what you're proposing would solve a very annoying problem, I think the cost to the overall enjoyability of the ship class would be too much.