Save the people who matter
Keep a list of the people and Pages you want to follow closely: customers, peers, people you want to learn from. Add their posts to your queue.
One post at a time
Work through the queue without the distraction of the feed. Read the post, decide whether you have something useful to add, and move on if you do not.
Draft in your voice, post it yourself
Spark Linky can suggest a comment in your trained style. Edit it, then post it on LinkedIn yourself so every comment is one you meant.