raw input transfers your tablet pen position to your game more accurately and with less lag. it makes a noticeable difference for me and is recommended to be enabled by the developer of the drivers i linked.
your fps latency is not input lag.
here's the thing with input lag. unless you're playing some crazy fast stuff, it's not necessarily a bad thing once you get used to it. some tablets like the h420 and the ctl490 have built in hardware lag and yet are still used to varying degrees of success by most players. input lag being present sets a physical limitation on how fast you can move your cursor, but so long as you're moving below that limit (and most of the time, you will be), it's just a matter of muscle memory and subconsciously adjusting to a different cursor velocity.
playing without input lag is still theoretically better, which is why i'd recommend it, but it's possible to play most maps fine with your setup. do note that switching between different levels of smoothing/input latency will take time for your muscle memory to recalibrate and get used to, and your aim will be early or late for awhile as a result.
so to answer your question on whether it's better: in the long term, yes. no input lag will raise your theoretical performance ceiling and let you play faster maps slightly more easily. in the short term, no, because it's going to take you a couple weeks to adjust and your aim is going to feel awful until then.
if you're just playing for fun and/or aren't concerned with min maxing hardware performance, then stick with whatever feels good. if you want every small advantage you can get, then you should switch. just be prepared for a rough and frustrating transition period.
(I'm being ironic and sarcastic don't take it personal or harsh)