1x4 Doujinshi
Pooh Farm - Flamingo Nobeko
Pooh Farm's doujinshi works are amazing. Her (their) known doujinshi are all Quatre-centred epics, whether it is 1x4, 2x4, or 3x4. Although she does seem to prefer the pairing 3x4 to be the foremost in her story. The 1x4 works I know of are Just A Hero,
Eiri Asato & Sohya Izumi
Again, Eiri Asato is another doujinshi artist favouring 3x4 the most. Yet I have found two 1+4 doujinshi co-created with Sohya Izumi. They are Glass Globe 1 and 2.
Tsugumi Nanjyo & Mizuki Takami
Tsugumi's drawings seems so ... well, everything is just right! it seems so puts enormous amount of work into making all the lines smooth, the proportions right, and everything so... well... technical if that's the term. I love it! (the front covers below are all done by her!) Heero is so well muscled, he definitely can protect Quatre better than anybody else.. She had also done a number of 2x4s.
Mizuki had also done quite a number of 3x4x3s, her style is quite unique, slanted eyes and sharp lines is her technique. From the reviews I have read of her 3x4x3 works, her stories are generally very interesting.
You may find some complete doujinshi scans from these sites: