I'd say it was a toss-up, between China and India. China is developing FAST, but they have a lot of help from the US (intentional tech transfer, unintentional tech transfer, and traitorous bastages selling them info) and from other nations like Russia. India is pretty much rolling their own due to sanctions from the US because of India's nuke program.
I'd give India the edge on innovation, but China the nod for rapid progress and active, successful, and fully funded development programs that actually do something new (for them).
Comments on non-winners...
Russia still has a lot of hardware that is reasonably affordable and reliable, but I don't think they're doing much of anything that is really new and they are relying on income from other nations to fund their space program. As for ESA... What's ESA done lately that's worked and was revolutionary? I'm not talking about lofting some neat new astronomical instrument into space... Anyone can do that. I'm talking about progressive stuff... I don't know when the last time was that ESA did anything that nobody else has done.
I won't even go into the US space program, except to say that a lack of focus and enthusiasm is fatal to a space program. Sending machines up to space is expensive but routine and not very exciting. Also, if you get to adverse to risk, you'll never do anything worthwhile. NASA needs to grow a pair and hire some adventurers to pave the way for the scientists who will use mature systems. But to do anything new and worthwhile you need adventurers and explorers who will take risks with their eyes open, and a management/leadership team that is willing to send them up with a higher margin for failure. We lost hundreds of pilots while developing our aeronautical systems since the pioneers like the Wright Brothers and Langley had their first fatal accidents. We've lost a mere fraction of a percent of the number of astronauts when compared to the same amount of time. Yea a space accident costs more than an airplane accident so the lost resources are greatly multiplied when you lose a spaceship compared to losing one airplane, but excessive concern over human risks are crippling NASA.
Rutan and his team won the x-prize flying a spaceship with a propulsion system that would never leave the drawing board with NASA, let alone earn a manned rating. The ablative nozzle used with spaceship one is effectively a random vectored thrust nozzle, due to uneven ablation. That's dangerous as hell. But they did it, and the pilots survived. Had they met with disaster, some funding may have dried up but they'd still have a list a mile long for volunteers lining up to be the next test pilot. That's how you run a space research program... You take steps to counter hazards and reduce risk, but at some point you light the candle and go for it instead of running endless simulations and design reviews until you run out of money or come up with a foolproof plan that isn't affordable. Every pioneer in every field of human endeavour for the last 2000 years would agree.