I've been looking into switching to HD wallets but there is still some things I prefer about vanilla bitcoin single addresses. I don't keep an wallet per se. I have my keys on cold storage and whenever I need to spend from them, I use mycelium feature "spen from cold storage".

I do not intend to radically change the way I use bitcoin as I feel that I have the amount of security I desire. However, I do want  to start using bip32 wallets instead and possible bip38 encription and possibly bip44 mnemonics.

So the first question is: How do I manually input randomness to a bip32 seed generator tool?
My favorite way of creating keys is manually feeding a very long string of gebrish to a brain wallet tool. I would like to do something like this, but instead of getting a plain bitcoin private key, I want a bip32 seed. If possible bip38 protected and in mnemonic format. I don't know if there is good support for combining these three. By good suport I mean, easily import it to a wallet software in the future. Or, even better, use something like mycelium's 'spend from cold storage' feature.

Another question is: How easy would it be to monitor the balance of an HD wallet?
I carry around the addresses on mycelium as watch-only addresses. I would absolutely want easy access to the balance while having my private keys secured somewhere else. I read that HD wallets have this number ( which name I can't recall ATM ) that is used to derive an address from other address. If I understand this correctly, compromising security of that number would only compromise privacy in the sense that the address hierarchy can be revealed, but the private keys would still be secure. Please correct me if I am wrong in here.
I do not mind managing those numbers with less security than my private keys, but one question still remains: how would easily check the ballance of an HD hierarchy of addresses? Do most wallets suport something like "HD watch only hierarchy"?

thanks in advance.