Should I use PFsense or OpenWRT?
I wouldn’t recommend pfSense unless you’re already invested in it (e.g. already have a pfSense setup and want to transfer your config files and settings over). Netgate (parent company) has been moving towards their paid versions (pfSense Plus and TNSR), the Plus version is free if you buy their router otherwise will cost you some money for a subscription. And meanwhile they stopped providing current downloads of full installs/builds of the free community pfSense so actually getting the current 2.8.1 is a hassle now - you’re expected to download their Netgate installer that needs internet access to download the full install while installing the router software, or you need to download/install an older version of pfSense (2.7.0 I think) and then get online to update it to 2.8.1.
Just went through all that doing a re-install, it’s crazy that I need to have internet access to install the router that will provide internet access LOL.
OPNsense is a well known alternative. OpenWRT could work too but I haven’t used it personally.
You didn’t mention your laptop specs but I’d say if your laptop has USB 3.0+ ports then you should be okay with plugging in a multi-drive USB DAS (like the ones with 2-5 drive bays) or even a single drive USB enclosure if that’s your preference. I have a few that I use on and off without issue.
Slower USB speeds are also functional but the performance hit will be noticeable.