I know that for us cluster feeds were really needed. Anna was always the most hungry in the afternoons and early evening so it made a huge sense for her and me to cluster feed.
As for the dreamfeed, I did that for a while too, but from today's perspective, I am not sure it helped her sleep longer. It really works for some babies and it doesn't for some. Those for whom it doesn't work, wake up often at the time or just before the time of dreamfeed. My dd has had a lighter sleep around this time and could easily stir and awake.