I defoliated an entire outdoor crop last year and it turned out great, neighbors had mold on their buds I didn't cause I had too good of airflow between the colas. If you can avoid it, I definitely would but say it's a very wet season you will want to get rid of a lot of foliage to prevent bud rot. I don't consider myself an outdoor grower though so I have limited experience, another pro I noticed defoliating heavily was predatory bugs were able to assassinate all pests with ease.
If your unsure then maybe start by defoliating the lower third of plants, as another commenter said though defoliation is more for getting artificial light into thick or tall canopies. The Sun isn't going to have an issue.
Here's a pic of how I do them indoors, I leave main vertical branches and prune/strip all the growth on the lower third, these were in week 2 of flower and since I grew the strain many times before I knew they had another foot of stretch. The lower stuff is just going to be scraggly garbage and hard to process.