nice work Lauri. I don't think there's a one size fits all for fasting. I would relax and try the different protocols you mentioned. Personally I found the 2 day (56hr) fast the least pleasant. It feels like I'm 'getting over the hump' in the morning and break fast. 3 day fasts (80hr) I like better and use them intermittently, usually ending on Saturday mornings. Longer for me get's to be a little tedious (up to 5 days for me) however I always feel terrific in the morning which is why I never end a fast in the evening. That's a personal preference.
Some people like Just_Jo and y0u have been eating one meal a day, every day, and that seems to work for them. If you look at what y0u eats you'll see a nice plate of protein and fats
My experience is limited here so perhaps more expert folks can help out but I'd hover around the protocols Dr. Fung has laid out for starters.
EDIT: After sleeping on this I thought of a couple things that might actually be helpful in addressing your question, "...is there any way to know what the best plan is?"
The things I tought of in no particular order are:
1) What is a frequency of fasting that works for your lifestyle and your loved ones. Fung has suggested that the "24hr" fast works well for this as you can eat one meal a day with your family.
2) How "metabolically challenged" are you? Loaded question right? Longer fasting periods or a more aggressive frequency may be in order.
3) What are your weight loss goals? How rapid do you need to get to those goals? This may determine length and frequency of fasts. I have no particular goal weight in mind so I'm just experimenting myself to see what works, working being, "do I feel better or worse after and during fasting"
4) How much body fat do you have and how tolerant is your body to fasting? I think you need to have a little extra body fat to fast. I suppose when you get to or near your ideal weight, longer fasting may take on different meaning i.e. ceremonial or "cleansing" or body reset or whatever the new new age catch phrase is at the time.
and lastly, I put weight back on after a fasting period. This is normal for me. The general outcome is weight going down over time. If you don't like to see the scale bounce up and get panicky or judgmental about it, fasting will provide an opportunity to work on those issue
Helpful? Who knows
It looks like you are having fun learning, like me. Relax.