Depends on where and when travelling. How far between known reliable water resupply points.
I tend to carry more, rather than less. Been caught with "All the rivers are flowing" and found them bone dry, or "there's no water out there, you have to carry it" and found plenty of water.
Carrying it and not needing it, is way way better than needing it and not having it. I'll carry it.
Currently using a (heavy) pump filter and chlorine tablets. Filter to get the large nasties out, (which are also the ones that resist chlorine the most), and then use chlorine to kill the smaller stuff that makes it through the filter. This only needs 30 minutes of exposure time, which I don't think is that long to wait. If needed could use just the filter, or just the tablets, but prefer to use both.
Waiting on delivery of a Sawyer filter to make a light weight gravity system to replace the pump.
The Steripen is to much of a worry for me: Its fragile, needs batteries, light replacement, still need to filter, doesn't affect water in threads of bottles, photoreactivation, water turbidity, etc etc.. I prefer simple, easy replaced/repaired, reliable, hence my two step filter and chlorinate