Depending on the costs I'd consider dumping the Conqs and buying another Mastodon, but then that's my favorite model. If you keep the Conqs, check to see how much a Chain Fire Pod costs (Upgrades) and put one on the Mastodon if you can.
Use the Pumas as a flanking force. Double-move then down whichever side of the table provides the most cover so that your opponent can't shoot them up, then rush a group of models that are bunched up enough that their Flamers can overlap multiple targets. This strategy can wreck havok on a group of models grouped around an ECM model since the Flamer's AOE attack ignores the Jamming bonus.