I'll offer a slightly different angle on Twitter usage for baseball recruiting. I joined a few years ago pretty much solely so that I could plug in to college coaches accounts, with a few other baseball related follows peppered in here and there. As my son picked up interest, and gained his own interest in various programs and organizations, I thought it would be a good way to see what's going on in these coaches heads, and how they expressed that through social media, so I would add the ones he was looking at or that were looking at him. Turns out it was pretty valuable in that respect. I know – newsflash right – but it turns out that what folks put on social media, and what they like/retweet and who they follow, can indicate a lot about a person. Granted, not all coaches spend any level of time on social media but you can usually find an assistant or volunteer who does and they may reveal things about the program through their activity that you might not otherwise know.
As far as the promotion of my son via Twitter, it was very limited and nearly solely up to me to do as he really only was ever involved in snapchat and, to some degree, instagram. I might have retweeted a handful of posts made by his travel coach/org but nothing on my own. Best of luck!