Artemis was formerly known as Royal Princess, so you may be able to find more photos under that search. She is over 20 years old now & does show her age. Also, the passenger age list is more towards retired people.
If you want to try P&O then you may want to look towards Oceana (ex Ocean Princess) which is far more like the Princess product, or for a more British ship but brighter than Artemis, both Oriana and Aurora would be suitable.
We travelled on Artemis to the Norwegian Fjords last year & found her to be really friendly, and that we were treated as individuals rather than 'just a number' as can be the case with the megaships.
If it is the destinations that appeal to you, and you are happy to travel with retired people, then you might want to take a look at Swan Hellenic (the far more cultural sister comapny of P&O and Princess). Their ship Minerva II is an ex-Rennaisance ship & is really something to enjoy. The good thing about Swan is that ALL tours are included in the price of the cruise, so you can really make the most of the cruise.
Hope this gives you some thoughts, if you have any questions, please feel free to contact us directly.
Best of luck with your wedding plans,
Katrina & Alan
Last Cruise: Royal Princess August 2015
Next: P&O Oriana October 2015
Then: Queen Victoria January 2016
Golden, Grand(2), Caribbean, Royal, Sea(4+1 aborted)
Adonia(4+2), Arcadia, Artemis(2), Aurora(5), Azura(2), Britannia, Oceana(3), Oriana(11), Ventura(2), Victoria(5)
QM2(2), QE2(9), QV(6), QE, Caronia(2), Minerva, Minerva II, Fred.Olsen(8), NCL Jade, =X= Eclipse, HAL Ryndam, Aza.Journey