There is many day ticket lakes for carp - but I dont think quiet and day ticket for carp go together (if you know what I mean!)...
If you want picturesque then I have to say I love fishing Longleat you cannot get more landscaped than Capability Brown, but it does tend to get busy (especially in the summer months). But then if you only do it a few times a year like me you can accept it easier... also something about fishing and hearing lions, wolves and sea lions all in the same place, makes things more interesting! (not that close though)
In Bristol probably... Hunstrete lakes
http://www.bathampton.org/ being in the top 5!
Others I can think of... Woodlands (used to fish here occasionaly - few years back!)
http://www.woodlands-golf.com/woodlands_fishing_lake-29.html...also this place (down the M5) has had good feedback from friends
http://www.trinitywaters.co.uk/I am sure others can think of more...