This boat only had to sail in the English Channel - true it had to be able to fight the enemy - I think it would have been a trifle hazardous then though

I supospe it is also a far cry from the 'Bronze Age' vessels which sailed around the coast - from North Wales to Cornwall, for instance in order to get the 'Tin' from the Cornish tin mines and bring it back to Wales for smelting with the copper ore, turning it into 'Bronze'.
As an Island, 'boats' have been a requirement for survival - British people have had, to learn to navigate the high seas from time immemorial.

No they were too busy philosophizing

That I am not sure of. I cannot find a 'length' to compare it to The Mary Rose. They were built at around the same time (although at opposite end of the country - the Great Michael ordered by James 4th of Scotland & Henry 8th of England) The Mary Rose was originally, built between 1509 - 1511 at Portsmouth.
Then, along with many other big ships, the Mary Rose was rebuilt in the 1530s. Her 1536 rebuild transformed her into a 700-ton prototype galleon, with a powerful battery of heavy cannon, capable of inflicting serious damage on other ships at a distance. The high castles were cut down, decks strengthened, and she was armed with heavy guns, with 15 large bronze guns, 24 wrought-iron carriage guns and 52 smaller anti-personnel guns. The Mary Rose now had the firepower to engage the enemy on any bearing, and conduct a stand-off artillery battle. Some of the guns were mounted on advanced naval gun carriages, which made them far easier to handle and move on a crowded gun deck.

I have seen many paintings of this type of ship adorning the walls of 'Olde Worlde' pubs. They are great, I agree with you - such character.
There would have been decks - not too sure how many, but there would have also been the cannon deck - that was where a heck of a lot of injury's happened - when the cannon rolled back after being fired & of course the 'powder monkeys' - usually young women and children, who had to run the gauntlet between the gunpowder deck and the cannon deck - ensuring a stray spark didn't land on the precious cargo they carried in their hands

No Fredo this one was Scottish - then French