AppleAg, I wouldn't worry at all. I too read the reception threads on here and am shocked at what level they're at, and what's expected, and they start at 4!
DD is in junior infants and knows all her phonics sounds (c, a, t, = cat) and they've just started picture words (what's the correct term)?, words you recognise but can't sound out, from Len and Jen, such as 'like', 'goodbye', etc.
She can write all the letters but might make mistakes with l and j or b and d. She has a go at spelling things. She can easily write her name and her siblings names (she wrote her own Christmas cards this year), but her writing wouldn't be particularly neat. Her colouring is very neat, but she's extremely careful and takes her time, so as not to go outside the lines 🙈
She has always had a basic understanding of adding and subtracting, from doing things like grocery shopping. I got her the 'shopping list game' for Christmas (it's in Tesco) and she loves it.
I can't think of anything else.
I think it's important that they're getting on OK socially, are confident enough to ask their teacher a question, manage buttons and lunch ok.. Things like that?