I think keto may be best if you have a lot of weight you are trying to lose fast. Your body will eventually tell you whether or not keto is sustainable for you.
I felt great during keto. I reached a weight plateau about 40 pounds lighter than I was before and I stayed there for over a year. One month ago I started to think about calories, not carbs. I began to introduce things like fruit, oatmeal and sweet potatoes to my diet - things that would have been taboo on keto - with a daily calorie intake goal of about 1,600 calories. The result? I quickly lost an additional 6 or 7 pounds and seem to have reached a new, lower plateau.
Now I am aware of low-carb and low-calorie and try to incorporate both into my choices. It's healthier and more balanced that way. Another thing I've done recently is amp up my cardio exercise by getting both a new rebounder trampoline and a slide board. Along with the 20 minutes a day of strength training I do, I now try and add 20 minutes of cardio.
Exercise and healthy eating go hand in hand. When you are exercising regularly you are less likely to want to make bad food choices, or when you do you do so deliberately knowing that your body has the metabolism to withstand the occasional indulgence. And when you are regularly making good food choices, it can lead to a better sense of well being which can give your exercise a boost or the motivation you need to stay active.