Nick, if they don't continue this line, especially given the (seemingly) universal praise and lauding that Evolutions is getting, it will baffle me more than any other decision they haven't made over the years. There are so many possibilities with the line that could be explored, and to cut it short after three sets would be a real disappointment.
Now that we've gotten a "perfect" VOTC-level Obi-Wan from ROTS in the Pilot figure, they could do an Evolutions set with Episode I Padawan Obi-Wan, Episode II Jedi Knight Obi-Wan, and Episode IV Jedi Master Obi-Wan without them worrying about three Ewan McGregors in a box. Give them all soft goods cloaks, lightsaber hilts, lightsabers, an aquatic breather for TPM Kenobi, pilot headset and handcuffs/chain for AOTC Kenobi, a blast shield helmet and seeker droid (with clear stand, ala the Sith Probe Droid) for ANH Kenobi, and you've got a great set on your hands.
A Threepio Evolutions set could include SA versions of TPM Threepio, AOTC Threepio, and ESB/ROTJ Threepio. Throw in an assembly required Ewok Throne, a backpack for Chewbacca, a Battle Droid head and blaster, and maybe a Pit Droid, and you've got another great set.
And then there is Padme, and that just has a ton of possibilities for figures. From my figuring, we've still got at least 4 costumes from TPM, 10 from AOTC, and all but one from ROTS. If they did this as a "Portrait Edition in 3.75 Scale" set, accessories could be minimal and it would still be worth the 20 dollar price it would carry.
Luke, I think SA versions of Ceremonial Luke, Bespin Luke, and Endor Luke, with lightsabers, hilts, blasters, removable helmet, soft goods poncho, and cuffs would be a dream come true.
My other (pipe dream) wish would be for a Bounty Hunters Evolutions pack with an SA Aurra Sing (with blaster pistols and rifle), an SA Jango Fett (with removable helmet, switchable backpacks, blasters, and pilot headset), and an SA Boba Fett (VOTC sculpt with ESB colors and a removable helmet).
As can be seen from everyone else's lists and mine, there are still a lot of possibilities here and a lot of demand for them. Let's hope Hasbro is listening/paying attention.