As has been suggested above, products at the 'value' end of supermarket's own ranges might suit your needs.
However you might also wish to consider those products which are marketed for sale as baby flannels. e.g. Amazon.co.uk User Recommendation
(The comments there suggest that they're both very thin and also good for adults with sensitive skin).
I ordered them too ie the baby ones but I cancelled them. You like large - I don't - so these will do me lovely since I have had them before.
I don't like any thing large - can't bare large bathtowels or the next size down. Can't hold them - arms too weak. Use a standard towel for head, bum and toes LOL.