I am up for roughly equal trading based on value, as long as we're using the same price reference. I generally prefer to use TCG Market pricing.

The volume  of cards doesn't matter to me. I'm good doing 1-for-3 or more in either direction. Same goes for total value. I don't care if it's a $1 trade or a $50 trade.

I am perfectly happy with sending first, given my current very low feedback rating. If the trade is less than $20, I will simply send in a standard envelope with the normal soft sleeve and top loader. If the trade is over $20, I will pack the top loader into a bubble envelope and send with tracking info.