Yes, it is harder 'work' for some than for others to enter into the Rest of the Righteousness of Christ:
3 For we which have believed do enter into rest, as he said, As I have sworn in my wrath, if they shall enter into my rest: although the works were finished from the foundation of the world.
10 For he that is entered into his rest, he also hath ceased from his own works, as God did from his.
11 Let us labour therefore to enter into that rest, lest any man fall after the same example of unbelief. (from Heb. 4)
The point of contention here is that you are preaching the putting of more faith in
your work than in the Work of Christ.
We who rest in Christ are not lazy when it comes to the works God has ordained in advance for us to do; when we are ready (prepared ahead of time by the maturing that Grace brings), and when He directs, we obey and follow. It really isn't that complicated.
Mostly I think you're just judging folks inappropriately because they don't measure up to a standard you have determined to be the 'line', when instead you should be seeking to find ways to build them up in who they are in Christ, spurring them on to maturity so that they
can do the works that God has for them.
-JGIG