I have disabled pure server to try out some of the built-in cheats. I like using '/give all' but as soon as you die you lose all weapons. Is there a way to persist this throughout an entire map, even after respawning?
You could bind it to a key (ie, in your client's config file, /bind keyname give all) and press the key every respawn, but that might get tedious.
If you want the server to do this for you, you're going to need a server-side mod, I believe. The stock game doesn't support things such as this.
I think you're going for a CTF server, but Rocket Arena (or more specifically, the Clan Arena mode) is pretty much what you're describing. Rocket Arena 3 for Quake 3 is one good mod for this.
Another option would be to try and tweak OSP Tourney mod (download link there is busted, try here instead) to do something similar. They have a Rocket Arena-style mode, and it's likely that there are options for spawning players with non-default loadouts.
Beryllium also looks promising, you can generate a config file online and download the mod from this site.
There may be other mods out there that are easier to use and come with more features that you'd like, but you're going to have to do some searching to find which one works the best for your situation.