Territories against membership? NATO could apparently consider a notable Ukraine move. According to La Repubblica, a swap of territories would be the appropriate move to be remembered as the one who made peace possible.
All occupied territories were left to the Kremlin - but military aid was still needed for Kiev. The remaining part of Ukraine would eventually be included in NATO. In a final step, the new NATO eastern border would be fortified and upgraded. It is unlikely that such negotiations will take place before the presidential election in the USA.