Just to put my tuppance worth in. Sorry if incoherent.
Audit of staff (teaching and CA TA whatever you call them) existing skills. Look at their strengths and weaknesses. Identify where training is required from this audit.Draw up an Action plan.
Find out from your local authority (?) not sure how it works in England what courses are available and match to needs.
Identify need of children on register and which staff need upskilling in relation to those e.g. autism training, makatron courses etc etc.
prioritise needs - who is in need of training most urgently. Identify suitable trading and where/when you can access to it.
Run in school training on writing PLP ( again not sure of English name for what used to be IEP.) Some staff may need support with this. Again this can be identified from your audit.
Training for staff - broader spectrum training on Special needs , how to identify children who need help/ when to put a child on the register/ differentiation/ might be especially useful for young/ new teachers. Maybe suggest making a handbook for your school outlining processes where a child is identified as having an additional need. A lot of teachers seem to be unclear about the start to end process.
Training for class teachers in reading statements. Purpose of a statement. Legality of a statement . How to conduct annual review , write reports for parents/ Ed psychs etc.
Training for teachers in managing support staff for the benefit of the child with particular reference to statement if child has one.
Audit of exsisting resources/ identify gaps/ look where gaps can be filled depending on finances.
Difficult parents
difficult parents is a very negative perception and I would try to say that no parent is really difficult. They may as others have said be worried, anxious have had bad experience themselves. Important to build a relationship with parents , some may be as knowledgable as you or more about their child. Parents want to feel their child is the most important child in the school (feel - not is the most important child in the school). Be aware of language when you are speaking to parents. Don’t say I don’t really know your child (I’ve been on the other side of the table this year) Read all the information about each child so you are armed with knowledge and sound as if you know the child’s even if you don’t deal with them on a day to day basis. Be aware of the need to think before speaking.
Show respect for parents. Reflect on any interaction and why it went well or not and learn from it.
As I said SENCOs do not issue forth at birth and take up position. You may just have been unfortunate to have been in for positions where someone with more experience has gained the post. Hopefully a school will come along that is the right one for you.