Rob,
When you say the old name was developed through a deliberative process, my recollection is that we wrestled with the name problem at Costanoa until we were exhausted and thirsty. IPRMW was the least worst option on the table. We clearly have a different opinion about how well the old name has served us. I think most of us have resorted to referring to our group as the Pest Risk Workgroup or something similar in conversation, because I-P-R-M-W is unpronounceable in polite society.

Your point may be correct that we could (potentially) continue to grow the group without adjusting the name. However, we have an opportunity here to come up with a name that does tick all the boxes. Why would we deliberately pass up the opportunity? IPRRG (i-perg) encompasses the boundaries of our group, so it is inclusive. It is the most easily pronounced of the options put forward so far. It is visually compact.

Conveying the workgroup nature and other properties of the group to stakeholders and putative members is simply a matter of marketing.