If witnesses are already providing bitUSD fees then HERO feeds cost almost nothing.  It doesn't depend on any other data.  Providing feeds should not be considered an endorsement of or commitment to support any third party's secondary plans for the token beyond the features of the bitAsset protocol.

However, the current health of the HERO bitAsset is questionable and if the witnesses are given control of the feeds I think they should gradually increase the MSSR percentage also.  Since HERO is scheduled to appreciate, it consistently trades at a premium which often exceeds the MSSR, resulting in under-collateralized positions and a risk of failure.

*bump*

EOS is trading on a number of other exchanges, but not OpenLedger yet.  Why not?  Is this on the queue to be added, or have you decided to avoid it for some reason?

Price feeds are defined in terms of BTS, and BTS has been trading higher on Chinese exchanges recently than on other exchanges.

To hide accounts, click the gear in the top right corner,  open settings -> accounts, and click "hide" for the account in the account list.  This will not delete the private keys for that account.  Deleting the keys that control their funds is usually decidedly not what people actually want to do, so there isn't an easy option for that.  If you really want to lock yourself out of an account (transferring it to someone else, etc), you could change its keys from the account page, under "advanced features" -> "permissions".  If it's just an empty account that's irritating you, hiding it will probably be sufficient.

The decentralized exchange is built into BitShares just like the ability to make payments is built into other cryptocurrencies, so it isn't less secure than any other wallet.  What matters is how secure your keys are.  If you set your account keys to keys that you have in cold storage, then your account is as secure as a cold storage wallet because it is a cold storage wallet.  Technically your BTS in a cold storage account is still on the decentralized exchange, you just can't trade without getting signed transactions to the network.  If you use the OpenLedger website or other web wallets, your keys stay on your device (unless the people running the website maliciously alter the site to steal your keys).  Aside from that attack vector it's security is like a desktop wallet, and to eliminate that vector you just have to download the wallet yourself and run it locally.

In short, all BTS is always effectively on the BTS decentralized exchange, and that does not make storing it any less secure.

If you hold User Issued Asset tokens (like OPEN.BTC), you're dependent on the issuer's security and honesty to keep it redeemable for whatever it represents.  This is basically the same level of risk as holding BTC or BTS on a centralized exchange, except that arguably BitShares User Issued Assets provide less surface area for hackers to attack, since the exchange itself is securely on the blockchain and only deposits and withdrawals need to be handled by the issuer.

That's very strange.  What API node are you using?  Have you tried multiple?

If you're holding OPEN.BTC, you can withdraw it into a Bitcoin wallet through OpenLedger's Gateway service.  If you're holding BTS, bitBTC, or something else on BitShares you can either trade for OPEN.BTC first and then withdraw them, or you can use the Blocktrades.us Bridge service to convert and transfer in one step.  Both Bridges and Gateways are available through the Deposit/Withdraw button at the top of the BitShares wallet.  There are a few other Bridge services available elsewhere also, like Shapeshift.io and Changelly.com.