This may seem to be an issue theoretically , but if you see in practical terms, this has never been an issue for me. We just have to find people who are willing to play pvp and all the people are pretty much okay with adjusting their bet amount. Dividing people in various chat rooms of 0.1BTC, 0.001BTC etc would just distribute the people and soon you'll have all these 3 chat rooms empty. We aren't able to get enough people in a single chat room(pvp channel) and so collecting people for 3 different chat rooms seems to be an impossible task.
you are indeed right, but I actually happened to think of another idea, there could be a list of those who requested pvp, some sort of table, those who requested pvp will have his balance to be held and and his username will appear in a table, those who wanted to pvp can easily click on the table, since it is a table, there will be a filter option of whichpvp bet you are seeking for, but I think this might take up some consumption to the database
We'll consider this, having the option to send an offer to everyone would definitely increase PVP activity. I'm not too interested in adding some sort of PVP list, PVP needs to remain as instant as possible and offers should expire after a minute or less in my opinion.