Thanks Gadget, much appreciated. I've not had great luck at finding the (right) (and there were many) Powells in the Welsh Newspaper Archives. Despite being a reasonably good searcher in other newspaper archives. (In Australia they have a great one called Trove) (I text correct for them occasionally).
FYI, there's William Powell the Excise Officer, of Hereford and Abergavenny, his wife Rachel (who I think lived to a grand old age, she or her doppleganger was in the death notices). There's William's brother John Powell who lived on Llantillio Perthorey property, and I assume this John was father of the nephew John Powell since 2nd John inherited what his dad inherited. 2nd John Powell was a Navy Surgeon, based in Portsmouth. Definitely a surgeon early 1800s. And maybe late 1700s; he was on 2 vessels: the Vestal and the first Charwell (captured from the French and renamed Charwell).
There were also Powells in Abergavenny who were Attorneys at Law and had the same names of William, John and an additional Walter. I have their William's will as well, to cross check. They are probably cousins of some sort.
John Powell the RN Surgeon had a son called Horatio Nelson Powell who became a well known steeplechaser who trained as a lawyer in his earlier years. He is the one who figures most in newspapers. He was v. newsworthy in a calamity charmer sort of way: he maybe got drunk and attacked a cab driver when he was 23, he maybe 'frauded' someone else, certainly when he arrived in Australia quite late in his life, he was probably running from debts. In the short 10 or so years he was in Australia he clearly trod on toes and upset people. He ended up being thrown from his buggy and killed in the (then) rudimentary hot and dusty Murray River town of Echuca. (although in England it was reported as New Zealand). In his will he revoked the small amount of money he was going to leave his sister and her family - he said he was revoking the money as a consequence of their treatment of him the last time he saw them!
But I digress

Grateful for you to have a quick look, but don't go too far down the rabbit hole. There are way too many Powells down there...