Was Kant successful? Yes and no, according to P.F. Strawson in The Bounds of Sense. For example, Kant failed to prove the synthetic a priori truth of determinism, but his transcendental argument does establish the necessity for 'sufficient causal regularity'.
The important thing, though, is that Kantian-style transcendental arguments have a place in the philosopher's armoury. Wittgenstein's argument against a private language is a form of transcendental argument.
I've remembered something, though. Kant uses another argument, which he terms 'analytic', e.g. in the first section of the Grundlegung (the analysis of our ordinary notion of morality) and also in the Prolegomena where he analyses the notion of 'objective judgement'. Kant's idea seems to be that analysis merely discovers what is actually implicit in our conceptual scheme, or logic; but this still requires justification which analysis alone cannot provide.
And that reminds me that the main line of argument in my Naive Metaphysics is, or claims to be, an 'account of reality', in the financial accountant's sense of a stock check of our beliefs or concepts, which doesn't leave anything out. In other words, an analysis. The question of truth comes after.
Problem is, every metaphysical theory that has been put forward to account for the place of 'I' in the world fails the very first hurdle! You have to throw stuff away, discard data because it doesn't fit the theory. So my theory is the only theory left standing, by default, even though it requires one to accept the truth of a 'metaphysical contradiction'. The first requirement for a metaphysical theory, prior even to logical consistency, is that it saves the phenomena. When I wrote my book, I took this to be definitive, and uniquely true, of metaphysics.