I am a new student sport pilot with about 20 hours flight time, trying to learn to fly an Ercoupe 415 C with rudder pedals. When I finally get my ticket I am going to be severely limited in what I can rent, because outside of the tri-cycle Ercoupe and the newer LSA's....there are darn few planes to rent. The majority are of the J3 Cub tail dragger type, but very few instructors are teaching this art in my part of Texas.
If you're training in the Ercoupe, will it not be available for you to fly in the future? From a performance and capability perspective, it's not a lot different from a Cub. Taildraggers are available to rent in your area? There ought to be some CFI there to give you tailwheel training. It's really enjoyable training. Are you a member of a local EAA Chapter? If not, find one and get to know the mix and interests of the members. My chapter has a sizable group of builders, but an even larger group flying and sharing Cubs, Taylorcrafts, Luscombes, Ercoupes, and Flybabies, in multiple ownership variations. There's one operated as a club with a monthly fee and hourly pay-as-you-go format and a couple of others owned by 2-4 person co-ownerships. $5,000-$10,000 often buys a piece of an airplane. You can't get much cheaper flying than that.
.... is anyone pushing very hard to up the 1320 gross LSA weight so the Cessna 140's, 150,s and other Ercoupes will qualify?
Nope, and I don't think you'll see any significant effort in that direction. A few people are talking about it, but the FAA considers the issue done and the alphabet groups see other issues being more important and affecting more people, so you won't see significant action or support there either.