I get to fish once a month if I am lucky so I can't justify spending a lot on equipment. I mostly fish ponds and small lakes from the bank.  I currently bring a 7' MH casting rig with 30lb braid, a 6'6" M spinning rig with 12lb mono and a 7' ML spinning rig with 6-8 lb mono.  I mostly use the first two unless i want to catch some bluegill.  Three poles can get to be a pain in the @**.  I was thinking of going to a braid to leader set up so i can eliminate my spinning rod.  My thought is that 30lb braid with 12lb mono or flouro leaders will take care of most my needs.  I use soft plastics, spinnerbaits, and topwater( mainly walking baits and frogs). I dont mind to retie a leader to change to flouro or mono.  Am i on the right track?

Sounds great to me

Sound like a good idea. You could also bring some 15lb leader line incase you come into some heavier cover situations.

Just tie on a new leader and you're set.

Keep it simple and just pick one line. Seaguar InvizX #12 is my suggestion.