I've been feeling like it's the opposite lately. I'm super nice to Erik, the past week I've gave him medicine, completed all his quests, etc but he's wanted to move twice in a row. I'm now writing letters with gifts to all my favorites, but is it futile? I've been kind of rotten to one villager I really want to move out, but she's been there the longest and never has asked to move XD
What I've observed, and based on many others' experience, being nice to a particular villager (like what you did there for Erik), chat with them all the time, doing things for them, will *definitely* get them on the top of the moving list.
Yeah, kinda sucks but that's the game's design.
Now, as for that one villager you really wanted out, being 'rotten' to them, or hitting them with nets, or denying their request,
would only make them even more determined to stay and 'be better friends with you'. Yup. Bullying or hitting them won't work.
I've found that with Tammi in my main town, after seeking advise from other members on the forum, the best way (that worked for me) is to introduce yourself, chat a few times in the v beginning when they first moved in, then ignore them.
Within two weeks that horrible Tammi swiftly pinged and moved out.
Also, FYI in case this matters, the ones that you voided (as in not asking another player to come and adopt them to their town when they are in boxes)
will ensure that they will linger on your main street for all eternity.
How do I know this? Well, I was so happy to have Tammi & Rocket (argh) moved to the void, it did not occur to me that they will instead planted themselves on my main street and stores. Of course, I know better now ^^;;
The ones that I specially moved to my cycling town (either for adoption or voiding) did not quite show up much at all.