Yeah, if a journal doesn't work for you, just close it and start anew. Otherwise you'd end up with a fistful of journals .... oh. Wait.
Look, when it comes right down to it, you decide what's going in your journal(s) and if it doesn't work, just change it, scrap it or do whatever you want. I started "Bitesize" on the specific criterion that I would only review albums I had not heard before. I'm changing that now. Why? Because it's my journal, it suits me and nobody can tell me I can't do it. It'll make the experience better, for me anyway and hopefully for my readers, so why stick to a rigid format just for convention's sake? The main thing is to enjoy your writing, not find yourself constricted in a cage of your own making. Besides, it's fun to break the rules now and again, even if they're your own rules.