Besides some regional content on Byzantium, the main content of the Roads to Power DLC is the ability to play as a landless adventurer. You gather fellow mercenaries, travel around the map, and make money and gain favors by doing quests. This mostly uses parts of the CK3 engine that weren't even in the original game, the travel system of Tours & Tournaments. As a result, the landless adventurer gameplay feels very detached from the core game of CK3, as if a completely different game had been grafted on.

While your landless adventurer can gain favors leading to him becoming a count or duke, for example by marriage, and landed characters can become landless, this isn't happening all that often. Basically you play the landless part until you are tired of it, and then switch to the original gameplay. The transition isn't very smooth, and the landless adventurer part is clearly suffering from some limitations of the CK3 base game. Already the time scale isn't a good fit, you probably wouldn't want to play a mercenary group over the 600 years that a CK3 game can take.

I think a completely separate 30 Euro game about playing a landless adventurer in the middle ages would have worked better than a 30 Euro DLC that grafts this gameplay onto CK3. There seems to be very little synergy between the two game modes. And while I see why CK3 fans who got bored of the main game welcomed a DLC that is offering something very different, I wouldn't want games to become collections of sub-games with very different gameplay and little connection between the parts.