I'm not expert in Chinese a/c but it seems to me that J-7G with its wider LE flapped wings would reduce much of low speed drag problems on landing and else. 'Used to' hardware also lowers training and logistic problems. It could be new a/c instead of limited residual life used a/c. Price could be a factor, especially for not so reach countries.
I suppose that F-16s that would be offered to such countries would be early models at the end of service life. I reckon Chinese are not offensive country to West, especially, one need not to buy and became material junky of any block. Somebody talked about sovereignty. Let’s test it. Why should Romania need missile defense or F-35 ?? Security from whom ?? That JL-9 seems to be hundred times cheaper than F-35 yet still relatively modern.
Romania need to learn how to catch a fish, not to wait somebody to give it. Or first, to be willing to learn and work.