you can place them wherever you want if you have the time and willingness to prune as needed.Quick question can I add Zoanthids right next to The SPS in that rock at front? and between the euphillia coral?
Generally speaking LPS like Euphillia will grow larger and faster than SPS coral. Euphillia also has very strong stingers meaning they will obliterate nearby non-euphillia corals. Eyeballing your fourth pic with the torch- it seems okay to me - but not sure where that SPS is that you mention.