In terms of welcoming people there is an inbuilt solution already. Upvotes. It encourages people, whether it's a new user or an experienced one. I see no need to be stingy with upvotes, they cost nothing but a mouse click.
A recent question I answered had 5 other answers, I upvoted 4 of them, the chaps put in the effort and had reasonable answers, so at zero cost I gave them a small morale boost. My rationale is that we deal with people, the accepted or highest voted answer may not be the best in all situations. So it increases the visibility of other reasonable answers, and there is no downside.
The flip side is that I don't see any point in discouraging people who make an effort. So downvotes should be used more sparingly. It's axiomatic that a stronger and healthier community exists when people encourage each other.
I know this seems simple which is probably why no one mentions it, and most of you probably do it anyway.
Just my opinion.