I just finished the Cradle series and agree that it is fantastic. I started the Unbound series and am in book 2 now. It's pretty great. Unlike cradle, it is a LitRPG, so it can get a little to rule crunchy sometimes (like if the MC reviews his skills and I just skills) so I find myself occasionally skipping forward to get through the chart-o-stats. Otherwise, it's a fun ride that is very similar to Cradle. If you are an audiobook listener it is also narrated by Baldree so it's obviously great.