As the title says I'm looking for a good alternative for Heliboard. I've tried a few of them and:

• Heliboard is my favorite but the suggestions are a bit meh, sometimes it doesn't suggest correctly or does not auto correct me. Sometimes it does but sometimes it doesn't
• Futo is goat in suggestions compared to Heliboard but it doesn't have an much personalization as Heliboard (even if Heliboard isnt goat on that aspect). I can't change symbols layout based on my taste (or muscle memory tbh), themes are a nothing crazy IMO, I wish I was able to make my own but its currently set to "coming eventually"
• FlorisBoard was my first ever open source keyboard but at that time, it didn't have suggestions but placeholders so I uninstalled it because I need them

I'm looking for a few things (ordered by importance):

1. Multilanguage support for correction. Is it even possible? Before switching from Samsung Keyboard to Pixel + Foss keyboard, I think there was something similar but I could be wrong (Top priority but at the same time is optional if not possible/hard to have)
2. Great correction for multiple languages (IMHO Futo is superior to everything I've tried)
3. Customization: Symbols layout, I want to set my own symbols and "subsymbols" (? The hold to show more)
4. Customization: Themes. I want to be able to change the colors of the keys/background/etc basically how Samsung Keyboard is customizable with the Keyboard plugin in Good Lock (or some nice themes with limited personalization but I would love to set my own colors

Thanks!