It is a long way to the Maldives, so travelling in a premium class is well worth considering. I would certainly upgrade to WTP (and probably also to CW) but you will need to consider what the additional costs mean to you.
Although the WTP seat is a little hard, as many agree, I find the extra seat width and leg room make it a good option. You will also earn additional BA Miles, which might be useful and 75 TPs each way, if that is important.
It you can stretch to £1,400, then do consider the CW/WTP option, although the return journey will not be as fun as the outbound for at least a couple of reasons......
CW will give you lounge access at LGW, which is pretty good, although I have not been there recently and I understand that there have been some changes. The flat bed and improved catering etc should make this a very enjoyable start to your holiday!
Whichever class(es) you travel, have a good holiday!!