Lanakov and Sombs raise some good points, but on the whole I think Antonio's suggestions sound very interesting. There may not be a specific need for an interceptor class, but there certainly would be room for it. I really like tactical variety it could enable.
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This is of course not necessary, but would it be possible (and/or desirable?) to rename the ship class? Because after Antonio's revamp, they wouldn't really be "fighters" anymore, but rather... "Interceptors", or "Scouts", or "Light Support Craft", or something.
(And then the current HFs can be renamed, because they would be the lightest Fighter class; VHFs become the new HFs; and SHFs (which is a weird descriptor anyway) are renamed VHFs. Again, it's not necessary, but is it desirable?)