Lots of replies, but not a lot of product recommendations.
Netgear GS105 5-port Gigabit Ethernet Switch - $40
TP-Link TL-SG105S 5-port Gigabit Ethernet Switch - $20
There's no particular reason to choose one over the other. The TP-Link is cheaper, but some people like the darker color of the Netgear. Not sure it's worth twice the cost though.
The answer comes down to cost. LiFePO4 batteries have enough capacity that they can be held at 80% and still beat SLA on capacity. The problem is that LFP wins on gravimetric and volumetric energy density; two metrics that aren’t particularly important in the context of a UPS. It’s a large brick that sits on the floor.