Beginner seeking help (short version)

Hello,

I’m just starting to get into Meteor. Its the most exciting thing I’ve come across in a long time. That being said I am having a difficult time wrapping my head around some basic concepts. First of all I’d like to refractor a simple one-page site that allows user generate content into meteor. If I’m using social accounts to verify someone is a real person and give them the ability to edit/delete their submission, is DOS still a concern? I have a limit of one entry per user on there but in this realm I’ll admit I’m a bit ignorant to the threats.

The question I can’t seem to get to the bottom of is CSS front-end packages. It I wanted to use an admin like Orion which uses bootstrap could I still use Materialize for the front-end? Or would I just be loading up a bunch of CSS to templates that would use it because it’s all part of the app?