I think the real concern is to bring into EU a country that is not "ready". It's not a East vs West power grabbing fight as WSJ tries to make it. Corruption and rule of law would be two main issues for Ukraine and Serbia as well. Being in the EU has great benefits but I believe the ascension process is even more important b/c that's the time when the important reforms are made.
Skipping the ascension process/reforms makes no sense. The EU could learn something from its past mistakes and current challenges(Brexit, Hungary, Poland).