ZBDongle-E and ZBDongle-P are equally senstive to EMF/EMI/RMI so you still need to take the exact same actions to avout that. So you should still follow all these tips regardless → Zigbee networks: how to guide for avoiding interference + optimizing using Zigbee Router devices (repeaters/extenders) to get best possible range and coverage
The main difference is the Zigbee stack firmware. Silicon Labs EmberZNet Zigbee stack is better with some devices while Texas instruments firmware is better with other devices. Generally though many have reported that their experince is a little better with a TI CC2652P based radio adapter as a Zigbee Coordinator while the same people also reported that Silabs EFR32MG21 based adapters work better as Zigbee Router devices, and you are going to need more Zigbee Router devices regardless.
Personally I would however suggest upgrading the Zigbee Coordinator firmware to latest version before replacing it. The firmware that ships with all of them is old and newer firmware have many bug fixes and improvments.