How do you decide what's best for you? There's a couple of questions to ask yourself. For starters,How are your sides and back? That's the main question. And you can follow that up with 'Does it work with the style that's best for me?' Or you can work that backwards---'What style is the best for me? Are my sides and back thick enough to achieve that style?' Thin back and sides are typically going to limit you to short styles. But if you want to go with fuller style that medium or more than you'll need to have the density in your own remaining hair to pull it off. So if your own hair is thin and you've decided that best style to enhance your features is a medium density style then you'd better give some thought to getting a full cap. That means shaving the thin sides and back. It's tough to 'bite the bullet' but that's the price to pay.
Regards,
John