I'm surprised that I haven't found any large titanite shards yet, I'm still using a +3 weapon and I'm at C
of D
/ F
K
(half explored both).
Either I've missed them (quite possible) or this is another area where the game is more linear. Bloodborne was this way too where you had a more linear upgrade progression, and it seemed very gated as to when you were going to be able to get upgrade materials. Compared to DS1 where you could go several ways from the start and find high upgrade materials as long as you had the moxy to get them.
So far the game is playing like a 'best of' of the series, and it's been great - but I'm missing the choices that you have in all the other Souls games - even DS2 let you progress in several different directions right from the start, and where I am now is the first time I've had a choice in areas to explore. I really thought for the price the tower key from the merchant in Firelink was going to open up another area, that's really the only disappointment so far, other than that I have not a single criticism to say about it.