1. Most people don't like web wallets because they are so prone to phishing attacks unlike software versions(MEW is one of the crypto related websites that has the largest phishing attacks, and they are trying to move away from the web based wallet. In fact, they don't encourage people to log in using Private Keys, Seed phrases or Keystore files). Do you have any plans to creating a  software wallet?

2. You should encourage people to generate their seeds offline using your wallet (it's a more secure way) just in case someone is watching since your wallet is browser based... It could be a malicious extension on the browser of the person trying to create a wallet.

3.  I was also not able to log into your wallet offline which make it less secure. Again, pick a leaf from MyEtherwallet: https://www.myetherwallet.com/access-my-wallet