If you don't like Kant, what do you think of Voltaire? He isn't conventionally thought of as a philosopher but had a nice bite to his words (ah, oppressed Frenchmen and the enlightenment period).
I'm afraid I have no opinion on Voltaire to offer because I haven't read any of his work :/
I
do like Kant though, despite the dry prolixity and contrived symmetry of his writing. He more forcibly argued the ideality of time and space than did Berkeley, finally putting his finger on its
transcendental ideality, its role as a condition of possibility for simultaneity and succession in phenomena, though, to tell the truth, I think the conclusion he draws from this, that things are in one sense determined (as their empirical character, or as the phenomena that are the representation in perception of their determinate movement in time and space) and in another sense free (as their intelligible character, or as the postulated unknowable 'thing in itself' which is the ground of phenomena), to be unfounded.
Schopenhauer, I think, more aptly characterized the thing in itself as "blind will", the
becoming (intrinsic existence of a unitary organic subject, a simple act of will) to phenomena's
being (extrinsic existence of a diversity of objects that reciprocally define each other in time and space, reflecting the conflict of wills), both one in the same thing of whose identity we become aware when we perceive volition/appetition/suffering, the phenomenal manifestation of the conflict of the will with itself that reveals to us our dual aspect as patient and agent. Not so much freedom as Heraclitean eternal fire.
Edit: Also, Schopenhauer was a much better writer than Kant, and really than most other German philosophers. His motto in writing was the saying of Luc de Clapiers, "la clarté est la bonne foi des philosophes" ("clarity is the good faith of philosophers"), with which I agree wholeheartedly. The words of a philosopher, insofar as their meaning is obscure, place the onus on his audience to 'infer' (really to conjecture based on a hermeneutical hypothesis) from them what he really meant and invites them, if they are prudent, to doubt that his ambiguity isn't a sophistical tactic designed to conceal the flaws in his doctrine and thereby usurp their affirmation and perchance their good will, exploiting their credulity to banal egotistical ends- in short, that he is not a common charlatan and a miserable obscurantist; conversely, clarity in writing demonstrates one's sincere willingness not to usurp but to present one's own beliefs for the frank analysis and- should the conceptual structures pass inspection in that they demonstratively conform to the subjective phenomenal structure, the 'me' that it is the task of philosophy (which is at bottom, recalling Montaigne, self-portraiture) to depict symbolically- prospective adoption of his audience so that, without wasting their time with fruitless hermeneutical speculation, he brings all involved nearer to the truth.
