My advice; try HTML Forms if you have rather standard contactform-like forms and you’re not looking for something fancy (which CF7 is not either), try Formidable if you need drag & drop form building or if you (will) need more flexibility/ integrations.
Concerning the very short-notice release-announcement of WordPress 5.0 with Gutenberg for Dec 6th: I’m with Yoast;He has a great “should I update”-checklist and conclusion in this blogpost;
Is now the right time to update?
Can your site work with Gutenberg?
Do you need it?
So our advice boils down to: if you can wait, wait.
So if you have a busy end-of-year, if you’re not 100% sure your site will work with Gutenburg or if you don’t really need Gutenberg in the first place; wait (while WordPress 5.0 stabilizes with some minor releases).
integrate all “pro” features (that’s right, free for all)
include some rewritten code for easier maintenance
be fully i18n-ready (lots of strings to translate :-) )
I will provide support on the wordpress.org forum (be patient though, I don’t have a deep understanding of code, functionality & quirks yet). I also have some more fixes/ smaller changes/ micro-improvements in mind (well, a Trello-board really) for the next release, but I am not planning major changes or new functionality. But I vaguely remember I said something similar about Autoptimize a long time ago and look where that got me …
Anyway, kudo’s to David for a great plugin with a substantial user-base (over 30K active installations) and for doing “the right thing” (as in not putting it on the plugin-market in search for the highest bidder). I hope I’ll do you proud man!