Allowing it to dry well will help if it's an issue with rotting roots, but those spots in the top pic aren't what overwatering or too dry usually looks like. When Pothos gets too dry, entire leaves turn evenly yellow, starting with those nearest the roots. Some of the damage in the 2nd pic could be from rotting roots but impossible to say for sure from a pic. Just in case it is some type of fungus, try to keep the foliage dry when watering. Pothos researchers at FL U say sudden drop in temps can cause spots like that. My (main) plant that didn't get brought inside seems to have suddenly developed these spots too since we've had a few colder nights in the midst of much warmer days. (There are some more interesting cuttings I've gotten in trade recently and I've lost interest in devoting space inside to the ubiquitous one. Curious at this point if it can survive winter here, so put it in the ground a few days ago. Last winters' experiment of whether it can go 4 months without a drink was successful, though my house isn't as dry as most during winter.) Symptoms - Leaves have scattered brown patches, usually located in the center of the leaf. Control - Low temperatures or abrupt change from very high temperatures to moderate temperatures can cause this discoloration, especially if plants are succulent and growing vigorously. Maintain even, warm temperatures. Here is a link that might be useful: Pothos production guide, UFL

That looks like scale. I have a lot of the exact plant and had to remove some leaves because I asked same question and that's what I was told

Possibly a soil minerals related problem. If it is growing actively now maybe you should fertilize it. It wouldn't be expected to do well without any fertilizer at all. A typical annual routine would be frequent watering plus fertilization in summer, with greatly reduced watering, no fertilization in winter when the weather turns dull and the plant becomes less active. With re-potting into a larger container filled with fresh potting medium in spring, as needed. (Also you don't want to leave the base of the pot sitting in water for extended periods).

Plants that are struggling seldom give you cuttings that will root, so it's a good bet that any attempt at starting cuttings would be an exercise in futility. New leaves on ficus are typically a lighter shade of green than more mature leaves, and it's not unusual for anthocyanin to express itself (the purple pigment dots) in new leaves. It will fade as the leaves mature. If the image represents the roots current condition, I don't see why your tree shouldn't recover quickly, though you might have slowed recovery down if you didn't keep roots dripping wet throughout the procedure. It only takes a minute or two for fine roots to dry out and die. Closing your tree up with only a low light source might well have caused a corky layer to form where the leaf attaches to the stem. This is called an abscission layer because it's the point at which the leaf abscises (separates from the plant). Once this layer starts to form, it's not reversible, so some of the lower leaves might still be shed. You have a LOT of leaves on the plant for the root system to keep hydrated, so you might also see additional shedding as a drought response due to a compromised root system. This would be do to the repot, but the roots drying out during the repot would add to your shedding woes. You could remove some lower leaves or just let the plant decide what it needs to do to balance the top to what the roots can keep supplied with moisture. As long as you don't over-water (moist or damp as a wrung out sponge is what you should aim for) your plant should do the rest. When you're sure it's pushing new growth, you should start fertilizing. HOW you fertilize, solution strength and frequency, depends on your soil and how you water. Key, is your choice of soil and making sure your watering habits are appropriate. If you're able to water to beyond the saturation point, so you're flushing the soil when you water. without the plant having to suffer because the soil remains soggy for extended periods, you already have half of the battle won. Al