The pale shells on their own are no problem - a hen will gradually run low on pigment over the laying season and her eggs will get paler. After she takes a break from laying, the new-season eggs will often have darker shells again.
The runny white on its own sounds like it's not a problem either, as Joyfull has the same with her older girls.
But once you add feather pecking into the mix I do begin to wonder...
Feather pecking can usually be triggered by a couple of different things - boredom and/or a nutritional deficiency. The deficiency is usually protein, although it could also be other trace elements.
There are a few things I would suggest you could try:
- Change their brand of feed - get another brand of layer pellets, initially mix it in with your old feed until eventually they are only eating the new feed. Keep them on the new feed for a month and see if anything changes.
- Add a multi vitamin/mineral mix to their diet. You can get special vitamins for birds, or I understand 'poultry spice' includes a multi vitamin (we don't have it here so I have no direct experience). In countries where we don't have specific avian vitamin products, a lot of people use products designed for horses! Obviously you would only add a sprinkle on their food each day. Again, keep it up for a month and see if there is any difference.
- In addition to the feed changes, try some environmental changes. Have the chickens got places they can hide/explore/get up off the ground? Try giving them a hay bale or a pile of leaves or wood chips to play with and see if that changes their feather-pecking.
Ex-batts are a special challenge because of there genes and the environment they lived in before you got them, so it may be that none of those things makes any difference to them. On the other hand, there is no 'down side' to an enriched environment and a few extra vitamins in their food so I think it's worth a try.