This is copying and deleting, not merging. It requires a pen and paper to make sure you get all the connections and info transfered.
Please give us a screen to move the info from one record to another by selection of the field at the least. I.e., I can move the death and marriage info from one card to another in a merge screen. I can get here by going into a "People" list and selecting a card. Then select "merge with" and display a list of records with a search. Once you have the two "People" records. Show the two card fields as a list right-left list and let me select an arrow on marrage, death, children line to move the info over to the card you want to keep the info (removing it from the other).
This would be a great tool to copy info out of matching cards in other trees in "Smart Matches" section.
P.s. I bought a subscription because you export the GEDCOM and the photos. Thanks for this feature.