I don't think 4-part vocal stuff will help in jflash's case. That would most likely make all of his contemporary music sound like hymns, since hymns are played as 4 vocal parts on the organ or piano. He already should have this option (called hymn sheet) on SongSelect, but I've not found a use for it.
There are a couple of things I would recommend, unfortunately none of them are an "easy fix." Stick with me, this post is a bit long, but I hope it will help. I came into my present Worship Pastor position earlier this year and I've needed to produce more sheet music than I ever have in the past. So here are some things I've done with my people, specifically keyboard players:
Evaluate each person's strengths on the instrument and attempt (when possible) to match song choices with that person's strengths. I have a pianist who is fantastic with notated sheet music but was almost illiterate when it came to reading chord symbols. I try to pick music for her weeks that utilizes more of the written-out arrangements the team already had in its pocket before I got here. This has also worked well for me with color instruments like flute and violin who already had some parts worked out.
Don't be afraid to recommend your musicians to further training, especially when you can point to a specific resource. I have recommended a couple of pianists to pick up a book that help them play with chords, called How to Play from a Fake Book. (There are two books with this title on Amazon, it's the one by Michael Esterowitz. I tried to post a link but I have too few posts yet to do this.) Alternately they could look through a "chord approach" method book, but those are a bit too simplistic. Bottom line -- any learning materials that help them to learn and visualize chord forms is good, but something that helps them to put those chords into useful movement is better.
This is the most expensive of my suggestions, but for me it has been worthwhile. I had the church buy a copy of Sibelius music notation software for me to use in preparing parts for my sheet-music-musicians. It has saved me hours and hours and hours because it's so easy to use. AND, what I like best about it is that I can put whatever notes I want on the page and hear the computer play it for me, allowing me to write parts for instruments I can't play well (or at all). I wrote a 24-bar piano and violin interlude one week to join two songs together that sounded great...but I couldn't play any of it myself. I just put the notes on the screen and the computer showed me what it would sound like. The software is between $400-500 but as I said it has been worth it for me. I used to use Finale Print Music (around $60-80) but there were so many limitations and it wasn't easy to use at all. This software has allowed me to give parts to instruments that I shouldn't even be able to write for based on my playing ability, and I highly recommend it.
Any of these things will help -- all of them will help A LOT. Good luck!