I've been using the Dunlop tortex picks for years. I generally go with .73mm, .88mm, or 1mm. I'm not sure they have any impact on the sound but I like the texture, it isn't just a matte finish, it's almost velvety.
I just set one up over the weekend using a VPS from cloudfanatic.net and a domain through cloudflare. Haven't opened it up to the public yet so I can't say how it would hold up for multiple users but I've only invested about $40 for a year of service so it's not a major hardship if it doesn't work out.