^ It's that foreign BO BvS needs to get more of next time. Compare the grosses of the following films.
MOS:
Domestic gross $291,045,518
Foreign: $377 million
Thor TDW
Domestic: $206,362,140
Foreign: $438,421,000
Captain America TWS
Domestic: $259,545,867
Foreign: $454,317,000
Superman out did both Capt and Thor domestically but came up short internationally. This with TWS and TDW being the second solo film of both Capt and Thor. As well as being their 3rd theatrical appearance when you include Avengers. Without a doubt BvS will be bigger. Not just domestically but internationally. Now that the market is acquainted with the franchise, there will be a larger demand to see a MOS sequel.
Also MOS sold more copies on Blu-ray and DVD than IM3. Iron Man being the highest grossing comic book movie of 2013. It was the highest grossing film of 2013 before Frozen came out on Nov 27 2013. Although a large part of Frozen's BO probably came in during 2014.
IM3 DVD+Bluray Sales: $77,662,837
MOS DVD+Bluray Sales: 101,187,705
So the MOS franchise definitely has legs and room to improve. It's just fighting an uphill battle for relevancy in a market dominated by Marvel, Fox (X-Men) and Sony (Spider-Man).