I've only given Linux 6GB RAM at the moment, and it's working out fine. Currently running Ubuntu 19.10.
I picked VMware Fusion originally because it was reported to have good-ish support for GPU emulation that was compatible with Linux desktops at the time. Without it, graphics can be a bit clunky. With it, it feels smooth enough for me, as a desktop.
My browser is Firefox on the Mac side, but dev web servers all on the Linux side.
The VM networking is fine, but I use a separate "private" network (for dev networking) from the "NAT" network (outgoing connections from Linux to internet), so Wifi IP address changes in the latter don't disrupt active connections of the former.
My editor is Emacs GUI on the Mac side (so it integrates with the native Mac GUI - Cmd-CV cut and paste etc, better scrolling), although I can call up Emacs sessions from Linux easily, and for TypeScript, dev language servers etc., Emacs is able to run them remotely as appropriate.
Smoothness over SSH from iTerm is a different thing from graphical desktop smoothness.
When doing graphics work (e.g. Inkscape/GIMP/ImageMagick), or remote access to Windows servers using Remmina for VNC/RDP, I use the Linux desktop.
But mostly I do dev work in Linux over SSH from iTerm. I don't think I've ever noticed any smoothness issues with that, except when VMware networking crashes due to SMB/NFS loops that I shouldn't let happen :-)