User management

[MAC]

Hello, I own a website to which I recently added (or integrated) a wordpress for news and articles management.

I plan to add some user value prizes and would like to ask if wordpress is ok for this or better think on drupal.

What I need is a sign-up form, and a shop player where players can spend their points earned with our promotions like freerolls or actively using the website.

Can I have this with wordpress? Is it secure enough or will I have spam or attacks everyday

BTW, I hate joomla.