Mine pecked like crazy at my grape leaves this summer.. just the ones on the ground. My pepper plants.. laaaaaaaaa... they liked to just do one chop down at the base and the whole plant would fall over.. leaving just a stump lol. I tried to banish them from the garden but failed this year.
I do like the coop plans. I was trying to figure out how much square footage is for the actual inside part of the coop. I think it is 3' x 6'.. which is 18 square feet. The run is nice because it is covered so the rain won't make the ground so soaking wet. The hardware cloth is nice.. it goes all the way around. Make sure to use hardware cloth instead of chicken wire. Predators can tear through chicken wire easily.
I like the idea of the vining plants growing up to provide shade. Chickens like to fall over and enjoy the sun, but mine love to stay in the shade more. Depending on where you put the coop.. you might need to add in a little bench in front or something just to give a bit more shade. You'll know once you get the little ones what they will want by their behaviors. You'll want to make sure that the coop is nicely vented. It looks like they have a window at the top on the right side (inside the run) that gives some ventilation. You may want to add a bit more.
Also.. the door swings out. There is some discussion about whether a door that swings out is better than one that goes up and down. Since I'm assuming you aren't going to automate the door opening in the beginning, I wouldn't worry about it too much.
Another thing to consider is.. is there a side door or back door that opens so you can easily clean out the coop or get one of the birds out of the coop if they are sick. That is very important. Keeping the coop clean is a regular thing and you'll want easy access to all areas.
I do think that you could fit 5-6 comfortably in there. Please keep in mind that there is such a thing as 'chicken math'. You can google it if you want. I think I may have seen your flock grow slightly as this thread progresses.. which is perfectly normal. We all start with wanting one or two chicks but then.... CHICKEN MATH. **sigh** I think the chicken chick said in a recent blog to always build a coop bigger than you plan to use. I wish I would have taken that advice. It is very easy to start with the intention of just 4.. maybe 6.. and then there is this darling thing down at the local feed store.. but you have to buy them in pairs because they fit into the flock better that way... and o wait.. that nice breeder on facebook is finally putting up some of her fancy birds that lay the dark green eggs.... and soon... there are more. It's easy to rationalize getting a couple more.. because a 'coon could take out a couple and then you wouldn't have eggs....................... yea. guilty here. i have no eggs to throw...err stones.
When thinking about materials, you might want to consider coops that utilize 4' x 8'. Most plywood, osb board, and 2x4s come in that size, therefore you don't have to cut it to fit. If the plans are made properly, you wouldn't be adding on cost and your coop would be bigger... just in case........
I like the idea of ordering with a friend from a hatchery. Just make sure to decide in advance who gets what in case some of the babies don't make it alive. DO NOT let you kids open the box when it arrives from the hatchery. It's an exciting day and mine have all arrived alive in the mail, but some don't make it. This could be very upsetting for kids so just be aware. Also, if you are just wanting hens, make sure to order "sex'd chicks" as opposed to "straight run". There are a couple of breeds that actually show different colors at birth so you know for sure that they are girls. If they are called "sex'd".. that term is used lightly. It's not science.. it's an art form. The businesses try to look and see what sex the baby chick is, but 90% of the time they are right. 10% of the time they are wrong. They will usually refund your money or give you a credit for the next purchase, but be aware that you may end up with some roosters when you hear the crow.. and it might not happen for several months. I went with "straight run" which is unsex'd. Out of the 24 baby chicks.. only 4 were hens. I did a lot of rooster selling and giving away this summer. It's good to have a backup plan with what you are going to do with a rooster if one turns out to be a boy. My last order was from MyPetChicken. They allow for smaller orders and will sex out more of the different breeds. I ended up paying three times the price, but to avoid the heartache of my cute little hens crowing was well worth it. They are about 8 weeks old. One has spurs so I'm thinking that I have at least one rooster. **sigh**
I do prefer getting chicks as opposed to pullets who are laying or about to lay. The ones I raised from day one have been such a joy. The look at me as if I'm their mom. They run to me in the yard when I go in. The ones I've bought that were older just keep to themselves. That's just a matter of preference. I am trying very hard to work with the new girls to get them to like me. It has been a challenge so far.