The brand new AC86u is capable of 100MB/s reads and 90MB/s write on samba and it only had a 1.8GHz processor.
This is then on an eMMC flash storage and not on an SD card as on the RAPI, and on top of this that plastic routers
came with ASIC and/or FPGA`s that frees up the entire CPU and it is able to do more. pfSense is a x86 software
firewall and nothing more at this moment. An yes a small samba server should be not installed on it as I see it right
like other also do, but you will be able to get a NAS with OwnCloud, Samba, Download station and whatever they all
offers today, and connect it to your pfSense easy to get access from outside with a VPN connection.