Break Out Rooms

Fifty breakout rooms are the max. I have not seen a feature to increase the breakout rooms. So it looks like 3 to 4 to a room.

Thinking outside the box.
Option 1 - Send 100 people to the 50 rooms for 1-on-1 meetings while the remainder stays in the main room. After the initial one-on-one sessions, close the rooms and then let the remaining participants go to breakout rooms.  Maybe not the best plan, but that is all I can think of if you really want a one-on-one with over 70 to 80 participants. 
Option 2 - Run the meeting twice and limit to 100 people max per meeting. 

You are correct. I found this on Zoom's support pages. 
Note: Zoom Support can increase the maximum capacity of your account's Breakout Rooms to allow up to 100 breakout rooms, with a maximum capacity of 1000 per breakout room (depending on account limits). This requires ALL participants to be on Zoom client version 5.2 or higher - anyone joining a meeting on your account who does not have Zoom client version 5.2 or higher will be required to update to join the meeting or join through the web client. If your users do not have administrative control of their computers, this will require assistance from your IT Department to update the client. This also affects the pre-assignment limits, raising them also to 100 rooms and 1000 participants. 

The link is here https://support.zoom.us/hc/en-us/articles/206476313-Managing-Breakout-Rooms