One classic approach to handling patterns with 3145/1345/3154/1354 is to jump to three of a major (some play this as the stiff, some as the fragment). The immediately-observed problem, however, is that focus on a strain with extras is difficult. For example:
If Opener wants to suggest a slam move with a minor agreement, he bids the minor. But, with heart agreement, Opener has insufficient space to pursue that strain.
Consider, then, Minor Suit Stayman. Many will play that 1NT-2S, 2NT/3C/3D-3M shows both minors and a stiff in the indicated major, typically 5-5 minors. In that situation, we have an abundance of space, especially when Opener indicates a four-card minor, as the strain for slam is already known.
This structure might possibly be improved. I am concerned a small bit with interference with what I am proposing, but that might not be a large problem.
The simple idea is to first make the immediate 3M (1NT-P-3H or 1NT-P-3S) show the 5-5 minors hand, slam interest, indicating the stiff. Opener can resolve strain easily, by bidding the respective minor at the four-level, or perhaps Flags as RKCB with really good hands (meaning, 4H RKCB for clubs, 4S RKCB for diamonds).
Next, have 1NT-P-2S be the two-under minor or minors call. If Responder is weak, he has one or both minors. Opener will bid 3C with club preference (Responder passing with clubs only or both minors weak, bidding 3D with diamonds only weak) or 2NT with diamond preference (Responder bidding 3C with clubs only weak or 3D with diamonds only weak or both minors weak).
If Responder has the 3145/3154/1345/1354 hand and slam interest he bids 2S first, to isolate the sole minor that might be the strain for slam purposes. After Opener's call, Responder next bids three of the (short or fragment, depending on style) major. This way, space is opened up for Opener bidding the other minor as a flag if needed.
4C = heart super-accept
4D = diamond slam move
4C = club slam move
4D = heart super-accept
3S = spades agreed slam move
4C = both minors slam move
4D = just diamonds slam move
4H = RKCB diamonds
4S = spades, but really poor slam cards (might be Moysian)
3S = slam spades
4C = slam clubs
4D = both minors slam move
4H = RKCB clubs
4S = spades, poor slam cards (Moysian?)