Is there a bottleneck here

Is there a bottleneck here

I have run some tests on an IIS (on EC2 @ 7GB RAM + 20 ECUs + ~600MBit
upload) server using JMeter and I'm unsure if there is a bottleneck. It is
serving static content only (images, javascript). JMeter is set to emulate
browser behaviour which downloads all static in parallel (7 per user).
Test 1:
Set to simulate 10 users (7 concurrent connections each)
Averages
Connections = 32
Get requests / sec = 237
CPU = 1%
Bytes sent / sec= ~ 8.5 million
Test 2:
Set to simulate 50 users (7 concurrent connections each)
Averages Connections = 82
Get requests / sec = 236
Bytes sent / sec = ~ 8.5 million
CPU = 1%
The connections average increases yet the requests don't so I suspect
there is something causing a bottleneck. Should the server be able to
handle more requests per second?