Honestly, 99% about quake is all personal preference. Anyone claiming it's not has to wise up and stop jumping on the bandwagon.
When it comes to advice.. Most advice is also personal preference from the person giving the advice, sometimes it helps you, sometimes it doesn't, but it's still nothing but personal preference.
People recommend lower sensitivities, tho there have been people in the past and there are people in the present who have a very high sensitivity and are nothing less in terms of skill than people with a low sensitivity.
People recommend "low" fov settings, from 100 to 110, yet there are people with fov's lower than 100 and/or higher than 110, it's all personal preference, once you get that in your head you've saved yourself from a lot of unnecessary dilemmas and thoughts.
About the mouse2 keybind to jump.. I personally would steer away from that as the mouse is involved in the aiming part whilst moving as well and I feel like it's easier/more comfortable to turn 180 degrees when necessary whilst still going in the direction you were going and yeah.. It just feels way more comfortable, especially when you've got a ton of stuff to do at the same time movement/aiming/shooting wise. But, again, it's all personal preference.
There is one general advice I would give you.. Use QLPrism, it's a standalone program to launch quakelive with a ton of extra features, just go check it out.
Things regarding settings that are not personal preference but more like a must are the following:
cl_maxpackets 125 (you can use 63 if you want tho 125 is clearly more recommended)
another thing I might want to add to that is the in_mouse command but some people rather play with the accel from their OS (when they're on windows 7 for example) but I would say in_mouse 2 is really a must, it's the raw input of your mouse without any settings from your OS affecting your mouse settings/sensitivity (for example the accel you get with windows 7). But like I said, some people rather play with other values with the in_mouse command, for reasons I cannot understand as I don't see anything positive about having your OS (referring to the accel ofcourse) affecting your sensitivity/mouse settings in-game.
About peripherals.. Avoid laser sensors when it comes to mice. Yes, rapha played with the xai, maybe even still does but honestly, laser won't ever be as good as optical, especially not when you're using a cloth mousepad (steelseries qck+, ss qck heavy, zowie GT-F,..).
A lot of people recommend you to overclock your usb port when you use a mouse like the intelli 3.0 for example (I'm using one myself), you can do this, but then don't overclock it to 1000hz as 1000hz is unstable, go with 500hz, I personally sticked with 125hz (standard for the intelli 3.0) and it doesn't bother me in any way but yeah.. Just an important thing to know when you would decide to overclock your usb port for your polling rate from your mouse.
Keyboards, get a mechanical keyboard, they last longer and are of a way better quality than standard rubber dome/membrane keyboards. Also the anti ghosting and no key rollover features are a big + when you use a mechanical keyboard. What kind of key switch you use is entirely up to you. Some key switches feel lighter to press than others, some feel more stiff than others,.. You just need to try them out and decide for yourself.
Mousepads.. Plastic or cloth mousepads, it's completely personal preference. A friend of mine uses his table, a wooden table, he just made sure it was smooth and there, the guy didn't even need to spend money on a mousepad so.. It's really up to you, though I would recommend a mousepad of a reasonable size (qck heavy, zowie GT-F, puretrak Talent,..)
Monitors.. a 120hz monitor is really recommended, i don't own one myself (yet) but really, playing on a 120hz screen makes everything so much smoother and easier to aim, to keep track of your opponent,.. There are so many advantages to a 120hz screen compared to a 60hz/75hz screen..
Atm that's all I can really give as "advice".