Are there recognized restrictions or categories for spoonerisms?

I enjoy thinking up spoonerisms in my spare time and came up with "why, indeed" and "dyin’ weed."

But I don’t know if this can qualify as a spoonerism, because

1. although the sounds are switched, they are not the first sounds of each word
2. the "g" in dying is wiped out.

Would either of these disqualify my two phrases from being a spoonerism, and if not, are there special sub-categories for spoonerisms that aren’t straightforward?

ETA: another possible subcategory might be "In-groups grin. Oops." Where sounds aren’t swapped but rather the "gr" is shifted from one word to the next, as opposed to a more standard construction "See, well, we sell."