If I recall correctly, we already had a subject similar to this one once. It was about Catherine of Aragon giving Mary two sisters before Henry VIII choosed to divorce her. Can't remember what we said on the subject though...
Anyway, if Catherine were to be more successful in giving birth (Mary was her only surviving child out of six pregnancies), maybe Henry VIII could be tempted to divorce her later in hopes she would finally be giving birth to the son he longs for (she gave birth to two OTL, but they lived only a few days). Of course, if all she can give him are daughters, he'll probably loose patience and seek to divorce her in the end (which will lead to the creation of the Church of England if everything goes OTL).
Forced marriage for his daughters don't seem likely in my eyes, unless Henry VIII thinks it can give him a strong ally. However, OTL, Mary and Elizabeth remained unmarried throuhought their fathers' reign. Of course, with two more daughters, he might think of marriage to secure alliance, at least for the younger ones (who have technically less chances of getting the throne).
What is more interesting in my eyes is what this implies on the succession. With two more daughters born of Catherine of Aragon, this will have consequences on Henry VIII's will.
OTL, he wished to be succeeded by his son Edward, then by Mary and finally by Elizabeth (and that's how it went). This will have no consequences on Edward VI's position, but if Catherine gave birth to two more daughters, they would be included, relocating Elizabeth to the fifth position in the order of succession for sure. As for Mary, her position will depend on when her two sisters are born :
-If the two of them are younger, Mary will stay as number 2
-If the one of them is older, Mary will be ranked as number 3
-If the two are older, Mary will be ranked as number 4
And in those conditions, it would be interesting to see how those two more daughters turn out to be... Getting two carbon copies of "Bloody" Mary is possible if they are treated the same way and remain Catholic, but that's only one of the many scenarios.