You are very brave to post close ups of your hand dovetailing. I give you points for effort but your not yet ready for prime time.
The first thing I would do is change your layout. I think keeping the pins fairly skinny and the tails wide gives a more handmade look.
It looks like your angles on your tails vary. I think you need to buy or make a dovetails layout template. I made mine out of black locust. Kind of looks like a little "T" square except at an angle and has shoulders to rest against the end of the drawer side. As others have said, careful layout is paramount. I use a hard leaded draftsman's pencil (4H) and keep it sharp. IMHO it works better than a knife because its more forgiving and you can erase it if you make a mistake.
Poplar is a fairly soft wood and the fibers can crush easily. A sharp chisel is a must and not too wide, 1/2" is the widest I'd use even if you tails are 2" wide. If you cannot shave the hair off the back of your knuckle just by pushing on it with your chisel, it's not sharp enough.
I find it easier to use a dozuki in softer woods but I like a traditional DT saw for hard wood and it takes practice to get the technique down. A light pressure draw back at about 45 degrees to drawer side to get lined up and then a fairly aggressive forward stroke should cut the sides of your tails in about four of five strokes. I use a coping saw to remove most of the waste on through DTs and cut to within 1/16 of the bottom of the notch. If I'm doing a bunch of drawers, Ill cut the tails on my band saw with a fine tooth blade using a special sled with preset angle stops. Why not, the look is the same but is more accurate than doing it by hand. With half blinds you still have to cut all the sockets by hand. Angled joints are easier by hand because its just too complicated to set up using machinery.
On half blinds I clean out most of the waste with a fortsner bit on the drill press before I go at it with my chisels. On half blinds, I always cut the tails first and then use those to layout for the pins. On throughs it doesn't really matter which you cut first but you should always use the first to mark the second.
Lay out your tails so it hides the dado for the drawer bottom in the drawer front and back.
On softer woods I cut to leave some of the pencil line if I can because the wood will give a little but in hard woods I cut through the center of the pencil line.
Practice, practice, practice.