Sending to lines independently can easily lead to problems with monitoring, unless you've done a fair bit of prep work beforehand.
If you're running your bass through backline (with a DI to the PA) so that your bass rig supplies the monitoring you need, then running your synthbass through the same backline gets rid of that (potential) problem.
Yup, unless it's a 4/4 or has an unusually deep body for some reason.
If you were closer, then I'd happily flog you mine at a big discount (after testing, natch).
Maybe find another Basschatter up East Anglia way who has one and will let you try it?
https://www.gak.co.uk/en/hercules-ds590b-double-bass-stand/53065?gclsrc=aw.ds&&gclid=CjwKCAiA2L-dBhACEiwAu8Q9YKPCYFwLrMhaZRolmuh5gD5-SL4av8vcA3bYuAnV214oDuBgsUDEiRoCBrsQAvD_BwE
Whereabouts in the UK are you?
I've used one of these for years.
https://www.thomann.de/gb/km_stehhilfe_14045.htm
Built like a tank, easily adjustable and very comfortable, especially if you get the optional backrest.
Best set list software I ever found was an obscure product by a software house you'll never have heard of.
I think it was called 'Excel' or something equally silly.
Best thing is when you turn up at a jam with a bass that looks like you found it in a skip, and when all the guys with their Stingrays and Dingwalls and Sadowskys have been up and played root+5 for their three songs, you provide 10 minutes of aural chocolate ...
Different world now, with crowd-sourcing and loads of freebies on that there Internet thingy.
If soundmondo didn't exist then the Reface DX would be an awkward beast supplied with a wide range of fairly useless sounds as standard. A couple of hours on soundmondo and I have every sound I am ever likely to need (playing in general covers bands and a specialist soul band) and all with no need at all to learn how to 'tweak' any parameters, still less actually program anything.
Just slave it to a 76/88-key unit with the (supplied) midi break-out cable. That's what I do with my Reface CP.
I hate midi and don't even begin to understand it (AFAIK those are 5-pin DIN plugs) but even I could manage that much. 🙄
Crackling is usually caused by coating with olive oil and sea salt, and then whacking the temperature up very high for the first half-hour.
Hope that helps.