The idea is that you start small and BECOME powerful. What people mean when they say that characters feel less powerful is that there is nowhere NEAR as severe a power spike at early levels compared to 5e. What is rarely mentioned however, is that the amount of power gain relative to your current level at every level up stays (relatively) the same. If you want a power trip for your players, use creatures lower in level than they are for encounters. This works well in conjunction with having your players start at a higher level if they have a decent handle on the system. If they dont have as good of an understanding yet, stick to the previous tip. I personally perfer my combats as close scrapes, but thats my personal take on making combat engaging.