Depending on the particular usage, you may not need to use all SH25's. If your room is truly large enough to use the SH25 (most churches are not-except truly mega churches), then you could use the SH50CA as a lower part of the cluster. So maybe you would need only one row of SH25's for the long throw. It just depends.
The SH50CA is a SH50 that is perfectly arrayable horizontally and vertically up to 2 high. It is missing one of the 12" drivers, but this will be of no concern when you use multiple boxes, because the 12" will sum together where the horn has little pattern control. It is designed to go under the SH25 as a down fill type application or used with other SH50CA's as a main cluster.
Because of the good arrayability of them, you can run the upper boxes louder for the long throw seats and the lower row down a bit for nearer seats. You would have the same tonality throughout.