It seems to me that failure to perform will lead to a failure to "overcome" and does not auger well for the churches who don't get back on track. Good "work" is acknowledged and pleasing to God it would seem. I have asked non-Catholic Christians on these threads several times but never have received an answer.
Revelation is addressing the tribulation. If you are saved by Jesus' blood, you will not be in this seven year period of terror. Those that are alive in this period will have to overcome till the end but sadly, not very many will survive.
Good works does please God and He expects them from us. On this side of the cross, we do them because of the love he showed us by coming to this earth as a man, being beaten and nailed to a cross for sins that we have committed. We do them out of love, not out of obligation.