First of all, one of the best articles to read when you’re starting with the program is, IMO, this one. I highly recommend to take a look, it helps to clarify some of your questions, including why studying 200 new cards a day and reviewing 200 cards a day is not a good idea from the SRS perspective: in a week you have would more than one thousand cards to review, but since you have a review limit of 200…you would forget almost everything you have learned!
On the other hand, add-ons should work also on Macm but,as Rumo said, some add-ons don’t work with recent versions because they need to be updated.
Also: the settings are there to be used, there’s nothing wrong with tweaking the settings to suit the nature of your material or your style of learning, but if you want to modify them, you should know what are they for, otherwise it’s often a better idea just to keep using the default settings until you get more familiarity with how the program works.
Finally, the interval has nothing to do with the card limits. Maybe this graphic can help you to clarify some basic concepts, but once again I recommend you to carefully read the manual, in particular, this section.