You have great ideas. Unfortunately, no amount of advice is going to guarantee that anything will work. Every child is really different!! You truly won't know till you try it. If it were me, I would just make the change, and yes you may have some inconvenience for a few nights, but she'll adjust! She really will! They all do!
You can also use a reward system of sorts, such as giving her a sticker the next morning if she does a good job of staying in bed.
Our almost-3 year old started in her toddler bed before 2 because she kept climbing out and it was too dangerous. She will still get out of bed and it can be a hassle sometimes. But what works for us is for me to lie down next to her for a little while, read to her, and wait till she's really settled down, if not asleep, before I leave. Not my first choice, but that's what's working for now.
Good luck, and don't worry! It will work out.