if sinr and rsrp both good then there should not be any problem in physical optimization.
for throughput u can check below parameters
check site bandwidth because dl throughput depends upon resource block(check bandwidth 1.4,3,5,10,20 mhz)
check mimo is configured or not(should be open loop spatial multiplexing ,can check in tems lte serving window)
check rank indicator(should be 2)
check backhaul(transmission bandwidth)
2. if sinr is good neighbor site can not affect own site throughput(neighbor only affect sinr and handover)