Yes there is a Discord group- maybe @davemccoy can chime in with the invite link as I don't have it readily available.
Thesteemengine is a great Discord group for curation. I think you will like it.
UPvote number chsnges but not the $$ amount- reason is more than likely you have used up your voting power for the day/24 hour time frame. Keep track of what you have left by using this- https://steemworld.org/@lil-mich it tells SO MUCH on this page.
I never believe a single UPvote is a waste of time. If you go to the link above I left for you, you can scroll down to the recent posts and pull up any of your posts and see who UPvoted, who resteemed, who did what and by looking through the UPvotes, you'll see who visits your posts frequently. Just because your UPvote is not giving them monetary value, they see you coming around and liking their work and posts; yet, another way people start following or visiting more pages. You see names over and over, it will eventually intrigue them to see who you are. So that 0.00 UPvote just got you a new visitor.
I personally have never invested a single penny into steemit, steem or sbd. Ever penny in my wallet was earned by writing and commenting. Sure it may increase your SP, but just because you have SP doesn't automatically mean you'll get followers. I know people who have and will use their own money into steem, sbd, etc and that is a personal choice they made. I see it as an investment into themselves.
And never hesitate to ask a question. That's why I'm here.