The first picture looks like alveopora. The second could be an alveopora or goniopora. Both are LPS I believe. What other corals are you thinking of purchasing? Your lighting and/or parameters could be a deciding factor as well.
The long tentacle plate is quite impressive. Nice tank!
Update after six years! The tank has been moved once and neglected a lot. I am renewing my passion for the hobby and fixing my tank issues. My alkalinity had dropped to below 6 before I noticed I needed to pay attention again, start doing more water changes and start loving my tank again. I...
How long has your tank been running? Do you ever blast your rockscape with extra flow to remove detritis? How often do you deep clean your filters? Hopefully by now you have fixed your problem but thought these may be things for you to look at. Happy reefing :D