At this time, we will not be approving any increase to the 50 per day and 10 per hour limits on your account. For the vast majority (more than 99% of users), these limits have been shown to be suitable for things such as registration/validation emails to be sent by sites hosted here while preventing use of the service for advertising, spam, and phishing campaigns.
If you need additional email capacity or intend to send bulk email in the volumes you're discussing, you will need to consider external email services designed for sending bulk email.