I would generally link to the home page, but some deep linking to individual posts is also good. The question of what will rank better depends on what terms you want to rank for. You might initially get better results from linking to individual posts as you can target longer tailed keywords. Try and name the post something people might type into the search engines. Then mention this phrase 2 or 3 time throughout your post. Then you can link to it with the same anchor text.
Yes.. I can suggest you better to linking for homepage, category, posts. Sometimes it's depends on what needs and requirements.
Link to the home page, if your linking structure is good the rest of the pages will get indexed easily, if you have some pages that are deep in the hierarchy then you should target them individually.