I just wanted to confirm your toughts... Ip's are not stored in the blockchain... If you create a transaction and initially broadcast it to one or more nodes, these nodes could theoretically store your ip. However, these nodes simply do not know if you broadcasted a new transaction, or just rebroadcast a transaction you yourself received from somebody else.
It's a little different for SPV wallets, for example electrum. Theoretically, an SPV wallet does not rebroadcast transactions. So if an electrum wallet user is connected to an electrum node and sends a new tx to this node, the node operator could potentially store the ip together with the tx, so he'll be able to identify you (that's where tor might come in handy)

That's true, untill you decide to spend those unspent outputs. If you spend multiple unspent outputs funding several addresses, everybody will be able to link those addresses together. And with some clever analysis of the receiving address, the amount of outputs (change),... one could potentially start to trace you (like you said before, as soon as you filled in KYC info for a service and somebody is able to link you to this service, you are no longer anonymous).

A big exception to all this is the people that were ignorant enough to use a web wallet, exchange wallet, casino wallet. Next to making their clients vulnerable to loads of other attack vectors, the online wallet operator could link every address to a user.