Help! Trying to manage feeding multiple cats

I have five indoor cats. Patrick and Gordon are 6, Mark is 5, and Jonah and Justin are almost 1. I have had all of them since they were kittens.  Gordon will seemingly eat anything but has always been the most athletic and the leanest of them all. Patrick is also not too picky. Mark seems to only want dry food. J & J also seem willing to eat anything but Jonah is a BIG cat now, 14.6 lbs! He is definitely overweight but also solidly built. I discussed him in a previous thread and have stopped free feeding as I was doing for years. The question now is how to do "feedings" when some cats eat faster than others. Also I want to know what people think about Friskies wet food or Petsmart brand Grrreat Choice wet food. That is what I have been feeding the four who eat wet. They each get half of a 5.5oz can twice a day (so total of 5.5 oz each per day). So thats like $2/day for wet food, plus crazy amounts of litter, Revolution every 45 days, dry food for Mark (who likes Meow Mix and complains when I try other things), and occasional toys. The cat budget is nearing $200/month! 

I don't want any of them to feel they have to rush to eat so that another cat does not finish before them and then help themselves to others food. It is not impossible to feed them separately, but is definitely a pain because they are used to moving as a herd to the feeding area and I sometimes need to feed on the fly, not having 15 minutes to set up five different areas then wait for them to finish and let them all out again.

Somebody seems to have occasional diarrhea, as I note the occasional "cow pattie" when cleaning the litter box but I don't know who. Also there seems to be a lot of throwing up within close proximity to feeding. I have seen Gordon and Patrick do this sometimes, there could be others. All of them eat and they all drink from the fountain (they LOVE it!!) All seem active and "normal" (taking Gordon to vet this week as he has lost a little weight and peed down the kitchen sink drain right in front of me and has also pooped a couple of times outside the box).

Oh well, I talked about ten different things in this post. Was supposed to be mainly about the food and feeding. Thanks for all past and forthcoming advice.

I have 10 cats, 7 of which are kittens a few are a year old and a few are just under a year. The older cats that eat slower I feed in a separate room. The kittens all eat together because they share really well. The best thing to do with slow eaters is to isolate them while they eat. My oldest is very slow and a grazer, so i have to offer him meals multiple times a day away from the other cats. In terms of dry food, I would work as hard as possible to try and get that cat onto at least some wet food, but I would also really encourage you to upgrade his kibble because dry meow mix is one of the worst cat foods available. It's basically all corn and fillers and almost no protein, it's not good food, at all. I wouldn't be surprised at all if the cat eating meow mix is the one having soft stool. 

Here's a list of good wet foods, and good kibbles. Yes, good food is pricey, but my theory is that you will have less vet bills down the road if you invest in proper nutrition now. Remember, cats are obligate carnivores, so you want to feed meat, meat, and more meat, and not any of that other stuff that's not meat. Good luck.

http://www.naturalcatcareblog.com/2010/12/the-7-best-natural-commercial-cat-foods-so-far/

(not on this list anymore, but food that I think is still good that i feed is Merrick LID)

http://www.naturalcatcareblog.com/2011/08/best-dry-cat-foods-so-far/