I think the term "Kantian constructivism" as an oxymoron. Kant was a constructivist about mathematics, but not about ethics.

It is rational to choose the right means to your ends to develop very elegant abstract formal theories of rational choice, and then turn these into what look like moral theories. Philosophers tend to be ravished by the formal beauty of such theories, and they don't pay much attention to the fact that our human limitations make them pretty useless in practice, while the simple point about instrumental reasoning is too shallow to be of much real moral interest.

Fichte is concerned with freedom as non-domination.

What is central to morality is rational self-constraint (acting from duty), in cease where there is no other incentive to do your duty except that the moral law commands it.

That Hegel's theory is derivative from Fichte's does not prevent it from being strikingly original and of independent value.

Empiricist philosophy always tends to be anti-philosophy (and is often proud of it).

I think the contribution people make is not proportionate to their fame or success. In fact, I think the relation is often inverse.