Compare the China Southern and China Eastern programs. Also compare prices for your typical tickets; it might be possible to earn a lot more miles by paying a little bit more for a slightly higher fare code, although the tickets might need to be booked by phone or with a travel agent rather than on line. If four trips has been earning ElitePlus easily, that same travel should be close to earning Elite at 40%. Even with Elite, you would still get use of the CZ lounges in China and you can use the Diners Club lounges elsewhere. How much is a slightly more preferred lounge worth to you? It doesn't sound to me like switching to the AF/KL or DL programs is a good idea, although you might want to investigate KE.

Yet another idea would be to think about switching to a *A program. I'm not sure which partner serves WUH; Asiana, TG, and SQ are the main Asian members. Wuhan might basically restrict your choices to CZ or MU, assuming you want to avoid CAAC as well as the very new small Chinese carriers, but Shanghai airlines might be *A now.