I've not used vbox under ubuntu in a while, and use it literally all day every day, and honestly in the 10+ years I've used virtualbox, I've never found it complicated or broken, so I suspect some pebkac here.
Under ubuntu or arch that I use with vbox, it should create at least a Nat network and a local-only network, it's important to know what these are and do. NAT will NOT allow things to connect to you, Local-Only will as long as you share a network with it, and for your LAN as you said you need a bridge to a wired (ie. not wireless) nic. When I create a VM, I give a guest 2 nics, one with a bridge to my local lan, and a local-only. This way it shares a
192.168.56.0/24 network with my host, and I can always network to the host, even if we're both on nat, or separate bridges (think usb nics presented to the guest direct). I use NAT when I'm presenting a guest to a foreign network, ie a client network, usually for audits with my network management tools, then they never see it, only my laptop. Nice for hiding a useful linux box behind a windows mule at work.
Only time I ever have weirdness with vbox and nics are with my thunderbolt dock at home if it gets disconnected. Which is somewhat rare, but vbox will sort of freak out if bridged to the nic and it disappears. Sometimes shutting down and restarting the vm works (not a reset!), sometimes I've had to reboot to fix it, but I'll just go back to hiding it on a nat if that happens until I do reboot next.
I am a network engineer by trade, so I don't tend to break my own network often, and always can fix it, but I would still say you simply didn't have it setup correctly. I find vbox to be the most simplistic vm solution out there, why I like it despite it having the Oracle stink, but been a fan since Sun. If you have problems with that, life will get no easier outside of it for you.
-mb