Cornwall is lucky in the amount of online resources it has.
I forgot to mention that the Agness Warn who witnessed the marriage of Charles & his second wife is his married sister
marriage ref
Agnes Olver Penrose dec qtr 1838 East Stonehouse vol 9 pg 397 with John Warn on the same page.
There are more siblings born in Plymouth area after Joseph in 1816.
At the baptism of some of John & Joan Penrose's children, John is noted as John Junior. This may signify that his father was also John. A John Penrose abode Crypstone was buried 24 April 1784 in Braddock. And another John was buried 3 Dec 1811.
I can see no link with Lanivet area for the other Penrose family, apart from the baptisms in Cardinham 1779-1781.
Revd. John senior died in 1776 aged 62. He was vicar of St Gluvias for 35 years.
http://penryncornwall.com/lake.htmI was just checking the Cornwall Record Office catalogue for any mentions of John Penrose and found a reference to the will of Charles Vinincombe Vicar of Brixham in Devon, he left goods to his mother Elizabeth Vinnicombe and to his sister Elizabeth wife of John Penrose, his books to his brother-in-law, John Penrose. The will was written 4 July 1754 & proved 6 August the same year.
The record office holds many documents left by Elizabeth widow of John senior.
http://crocat.cornwall.gov.uk/dserve/DServe.exe?dsqApp=Archive&dsqCmd=Index.tclElizabeth Vinicombe made her will later that year & it was proved 9 Mar 1756. Her burial in St Gluvias 4 Jan 1756 has notes stating that she was the widow of John, clerk, sub chanter of the cathedral church of St Peter, Exeter
This looks to be the baptism in 1712 of the Elizabeth who married John Penrose
https://familysearch.org/ark:/61903/1:1:NYGF-D31& their marriage in 1737
https://familysearch.org/ark:/61903/1:1:NYGF-D31The Penrose family papers are all catalogued with a reference beginning BRA2509.
Also just spotted an old book about John Penrose "A Cornish Incumbancy" which you can get as a free pdf. There are many articles about him online.
It could be that your Penrose family included Vinicombe in the names to give the idea they were related to the rather grander Penrose family. I've come across other families doing a similar thing.