Gridcoin online wallet

I'm on the planning stage of gridcoin online wallet. I'll try to illustrate how I create new resources. Below you can see lists of features and interfaces I think to implement.

Features:

• Web interface
• 2FA
• POST API
• QR codes
• Captcha register/login
• Mail notices
• Multiple languages support
• Auto wallet backup

Tables (database structure):

• users - uid, mail, login, password_hash, salt, balance, register_time, login_time, api_enabled, mail_notices_enabled, withdraw_address
• auth_tokens - uid user_uid, token, timestamp
• wallets - uid, user_uid, address, received
• api_keys - uid, user_uid, key, access
• labels - uid, user_uid, address, label
• transactions - uid, user_uid, amount, address, status, tx id, add_time, sent_time
• mail - uid, user_uid, mail, subject, body, add_time, sent_time
• variables - uid, name, value, timestamp

Variables - used to change pool settings from pool interface:

• payouts_enabled - allows enable or disable payouts for all users
• login_enabled - allows enable or disable payouts for all users
• api_enabled - allows enable or disable API calls for all users
• global_message - text for header on every page
• news - news section text
• current_block - current Gridcoin block
• current_block_hash - current Gridcoin block hash

Web interfaces:

• Login/register page
• Balance - you can see your balance here, also can send some funds and view last 10 transactions
• Address book & send - address book, also with send ability
• Receive addresses & qr - list of all receiving addresses
• Transactions - list of all your transactions
• Settings: - 2FA, api, api_key, password, mail, mail_notifications
• Administration page - global options, news editor, client status

Forms (user actions):

• generate_new_address - generates new receiving address
• send - for sending funds
• add_address_alias - change address book
• edit_address_alias - change address book
• delete_address_alias - change address book
• apply_settings - change settings on settings page
• register - add new user
• login - check existing user and login
• global_enable_login - enable logging in for ordinary users
• global_disable_login - disable logging in for ordinary users
• global_enable_payouts - enable payouts
• global_disable_payouts - disable payouts
• global_enable_api - enable API calls
• global_disable_api - disable API calls
• global_message_edit - edit global message
• news_edit - edit news

API (almost all functions from block.io):

• send {address} {amount} - for sending
• get_balance - get account balance
• get_address_balance {address} - get balance of specific address
• get_new_address - generate new address
• get_my_addresses - get addresses list
• get_current_price - get current Gridcoin price
• get_transactions - get transactions list
• get_address_book - get all address book records

Gridcoin client interaction commands (not a complete list):

• getreceivedbyaddress - for checking user address balance
• listtransactions - for getting transactions
• sendtoaddress - for sending funds

How balance works:

• User balance is all received funds (getreceivedbyaddress) minus all sent funds (stored in DB)

If you think wallet need another features, you can write them in comments.