Why Would Someone Follow Me? Should I Follow Back?

Note there is a question at the end....

I'm tweeting these days. In fact, you probably started reading this because I tweeted out a link to it. In the process, I'm gathering some followers. And, of course, I'm also losing some because they realize what I want to tweet about is not interesting to them.

More importantly, I trying to determine who I should follow. Because I do this "for work" some choices are obvious. I don't follow the people involved in MLM (multi-level marketing schemes), or have content that is nsfw (not suitable for work). In contrast, I definitely try to follow those who are interested in the same technical areas I am. Then, of course, there is the grey area. Real people who follow me but probably will never have a mutual business or technical interest. I'm of the tendancy to follow them until they prove to be in one of the categories I don't (or can't) follow.

However, at the same time, I'm an introvert (and have a primary job that requires most of my mind most of the time), so it's real hard for me to keep up with all the people I follow, especially on those occassions where I get someone who tweets a lot on my list and they start drowning everyone else out. which is a real shame as it might cause me to miss something from another person who tweeted something that was real interesting that I could respond to or retweet.

So I was wondering, how do I get people who follow me (and would like me to follow them back) to tweet to @intel_chris some message explaining why I should follow them, as in what the connection will be. Do you think asking people to do that will add too much noise to the system?
Do you think I should just DM each person I follow back with that question? Will that seem rude and pretensious?