Just because your budget is $500, doesn't mean you need to spend that much.
I am in a similar situation as you, and started with a PreSonus AudioBox 44VSL. It's a good piece of kit, but the driver was a bit unstable on my Win7 machine and failed completely under Win10. That old driver is still the current driver, and even has a Win10 compatibility statement. Bah.
And there was the occasional time when I wished for just ONE more input.
So, I picked up a Tascam US-16x08 for $200 on a Musician's Friend Stupid Deal of the Day. Even at its normal street price of $300, it's money well spent. v1.04 of the driver fixed an issue in Reaper and has been rock-solid for me. So good, in fact, that I've made it my default Windows Playback and Recording sources. My old Bose PC speakers are in a closet.
It may seem like a lot of I/O, but the provides some real flexibility. For example, I have a condenser mic for vocals plugged into IN1 and a dynamic instrument mic plugged into IN5. The US-16x08 has separate phantom power enable switches for IN1-4 and IN5-8, so I have it enable for IN1 and disable for IN5.
I've also just picked up 4 more condenser mics that I plan to use to record a 13-member women's a cappella group at the local university. I've got the inputs for that unplanned session. No scrambling required.
Tascam now develop their drivers in-house. That was a big selling point for me, since the US-16x08 is a new device. Some of their older legacy interfaces with 3rd party drivers my be another issue.
Good luck!
http://tascam.com/product/us-16x08/overview/ EDIT: I should add that I'm running at the minimum ASIO sample size (64), and have yet to experience a glitch.