If you disregard extensions named *-dev, *-doc, *-locale, *-bin and *-modules-4.19.10-tinycore* then there are the following numbers of extensions in the tc-10.x repos:
* 32-bit 1,527 extensions
* 64-bit 1,539 extensions
There is another choice apart from 32-bit Core and 64-bit CorePure64 - Core64
Core64 = rootfs.gz + modules64.gz + vmlinuz64
This uses 32-bit extensions, but 64-bit kernel modules.
There is still a 4gb ram limit, but with Core64, each app can use up to 4gb ram as long as there is enough ram physically available.
Finally, if there are extensions present in the 32-bit repo, but not in the 64-bit repo, you can request that they be provided.