Use a 28mm brightline finder to quickly compose the shot and do the final framing with the camera 28mm frame which is actually pretty accurate.
M7 with 28/f2.0 ASPH You need that hood to get the best out of the lens which is REALLY fantastic! The lens is worth the compromises.
BTW, a .58 will not help how much of the 28mm frame which is blocked. This does not vary with v/f magnification.