When a child is displaying more problematic behavior in the home versus in another setting, it is somewhat of a red flag. You've indicated that he's angry and is also mean to his younger brother.
This sounds like attention seeking and volitional behavior. Even if it leads to negative attention, to him it is still attention. You've used the positive reinforcement and not he is still not improving as much. In addition, he is dealing with the tics. These can be anxiety triggered and his anger may be one way of him to deal with his frustration- displacing it onto family members at home where he feels safer than let's say at school. He may not want to draw even more attention to himself at school and is therefore displacing this at home. He may be also perceiving his younger brother as competition.
In this case, it may be helpful to entrust him with some responsibilities that would strengthen his sense of self esteem and belonging in the family. Anything tasks that you allocate to him you'd want to let him know that you believe in his abilities and that is why you've chosen him to do them. If there is a possibility for him to be involved in some activities where he can interact with others even in a competitive yet positive manner (as in sports or art/music depending on his interests) it would be a good idea to explore that option. At this time, he is still developing his sense of self esteem and deriving a sense of belonging by his interaction with peers and adults. You are also correct that he may need more than what you are offering at home such as professional counseling. It may be helpful if you look into that option to find someone who provides family counseling versus only individual therapy. You are making sure that he does not feel singled out or getting a sense that he's flawed and you only focus on his positive traits and praise them throughout the day. Even compliment him for something such as how he's dressed himself etc. Anything that draws positive attention to him and his abilities.
We have let him recently go to the local shop alone and walk ahead of us to a local pool, as well as gving him the opportunity to earn pocket money for chores.
He plays a lot of sports and did play the cornet but has given up saying he is rubbish.
I am exhausted at trying to find positive things to praise, I continual try to . . .
Perhaps family counselling is the answer but I fear he will feel labelled and feel he is getting more attention from the situation?
In family counseling, the family dynamics and how they affect each member of the family unit (including him) will be explored. He needs to feel a sense of belonging and equality at home. You can think of many things to entrust him in the home to help with. If he is acting mostly at home, it is indicative that the triggers for his negative/unhealthy behavior are to large extent found in his home environment. IT does not necessarily mean that you're causing it but how he's interpreting it. Adlerian psychology focuses on each family member in relation to the behavior of the rest. You may talk to him to gather what is going on. Not in accusatory way but simply saying- I notice sometimes you do not seem happy and am wondering what may make it better for you. That way you keep an open ended question and prompt him to give you his version. You don't even have to agree or disagree with his version just listen so he feels accepted and listened to. The book below is based on Adlerian psychology and it teaches an effective module to deal with difficult behaviors. If you're to make an appointment for counseling, you let him know it is for every one to learn to be happier and get along. You don't' say its so you can get better and he won't feel labeled. It's all in how you present this to him.
The Parent's Handbook: Systematic Training for Effective Parenting by Don Dinkmeyer and Gary D. McKay