I single hand my 48 about 95% of the time. In a gale, a thruster would be way down the list from a spring line. It was on the day I needed one. Don't get me wrong, I'd love to have a bow thruster, but it would be a nicety, not something to rely on. I have issues where bt's are used as a critical part of the docking experience. Where my boat is kept, I see a number of dock neighbors who literally could not get into their slip without the thruster. It's just blender blender blender, just getting into the slip. No!
That said, what I wish someone would invent is a marine rated trunk monkey. I'm so tired of threading myself alongside a dock with a stiff breeze blowing and no more than two feet extra fore and aft. Once with boats rafted out fore and aft, so very little room to work with. I tighten to sphincter factor 5, get my ship together and put on the show and actually get where I need to be. I have my lines set up, ready to go with a bow spring already carried aft. Some good samaritan, impressed, shows up to take a line. I clearly and loudly command to take that aft bow spring and just tie it off where it is. Every single time, they take the correct line, march it 40 foot forward and stand with it, watching the boat drift in the wind and send me into fend off mode.
Queue the trunk monkey!