This is a huge misconception. Many people think we profissional teachers are those who will be looking very serious saying sentences like "Open page X, do exercise number 1 please". Or that we spend 40 minutes explaining grammar rules. There are such teachers (And there are students that love those ones) but there are also those who adapt to the new world of learning languages and those who adapt to students' needs 

Here on Italki I am also an active student and I have hundreds of lessons and I can tell that there are bad professional and informal teachers who have no preparation or ways of teaching. 

Better thing to do is to give them a try and see who would suit you better and never just keep one teacher (informal or professional), always try new ones and choose the one you know it'll be good for you. That's the beauty in learning online, you don't have to sign a contract with a school and bear the teacher you don't like for the rest of the year or semester. 

It honestly completely depends on the teacher. I've had (and have) both amazing professional and community tutors. Some professional teachers are indeed very professional, others are worse at grammar than I am. Community teachers of course don't have to be good at grammar at all, but I've found a few that can even out-grammar  most professional teachers. 

How your 1-hour lessons should be structured depends of course on the work you do yourself at home. I personally do lots of work myself and use my lessons to both converse and have my teachers explain me whatever I'm having trouble with. When I schedule a lesson, I often tell my teachers what I would like to work on, so they can prepare something for me. So that all depends on you!