I love every feature on Opera GX, I've been using it since it came out and I simply love it!
I would suggest to add a feature that allows the user to add or customize the aspect of the saved sites in the Speed Dial tab, for example: YouTube, Discord and Reddit (1) have their logos displayed while sites like Crowdin, Bandcamp and Twitter (2) don't.
Can you add the option to add custom images like in Firefox?
(1)
(2)