Sturm und Drang is about as romantic as can be.
I beg to differ. Everything depends on how you choose to define the word 'romantic', goes without saying, but, historically speaking, German romanticism defines itself against both Sturm und Drang and Weimar classicism. Which may also be to say, it was influenced, shaped and defined by them just as it was trying to distance itself from them - and get over what it saw as the pernicious tension between their perspectives. Still, the romantics seem to have appreciated the later Goethe - the Weimar sage, that is - slightly more than the Goethe of Werther.
I'd definitely include Goethe and Schiller ~ but I'm using the term fairly loosely. I actually just read Goethe's novel, The Sorrows of Young Werther: I'm going to need a lot of convincing that that isn't the quintessential romantic fiction. I'll hear you out though, if you can be bothered.
As for the metaphysicians - well, it seems to me that Aristotle is a pretty central figure for the Schlegels, Hegel, Brentano and others, where the relationship between being and non-being is so important.
The Werther book is early, Sturm und Drang-period Goethe. The romantics didn't have too much time for it - Sturm und Drang wants to be 'sentimental' (in Schiller's, and neither the popular nor the 18th century British, sense of the word), which German romantics appreciated, but, they'd argue, it ultimately fails due to its inability to develop anything close to what Schlegel famously calls romantic irony. Which is an absolutely essential
aspect of romanticism - and one which people tend to completely overlook when talking about what they construe as 'romantic'.
Also, neither Hegel not Franz Brentano (the Brentano I spoke of is Claus, Arnim's friend, folklorist and mythographer) were romantics; Hegel had little but contempt for German romanticism - and perhaps the only 'philosophical' name to be connected with the movement was Schelling. Although he too took care to distance himself from the romantics.
Interestingly, Shelley, Beddoes and Keats (and Blake and Coleridge and Wordsworth) weren't romantics either, strictly speaking - by which I want to say, they didn't describe themselves, nor were labelled by their contemporaries, as such. And Shelley's masters were Locke, Shaftesbury, Berkeley and, especially, Hume . . .
Not very romantic, those romantics are - and not much romanticism in that romaticism