If so it would be better to make BCH claim after 10 August.
That's not necessary in any technical sense AFAICT. I can't predict prices, though.
Which one you prefer suggestion better, Install a BCash wallet on computer or use a Web-based wallet / wallet exchanges?
If you actually want to hold BCH for any length of time, I'd use a software wallet in which you control the private keys.
I am waiting for the arrival of my ledger nano s. I though that they had in a built in coin splitter, so my plan was just to re-seed the ledger nano s from my blockchain.info wallet. that would accomplish the same thing for all addresses in the blockchain wallet and then creates two wallets on the ledger nano s, no?