I am going with Robert's suggestion of the Canon EF-S 17-55mm f/2.8 IS USM Lens as a first choice. You can't go wrong with it. But I do think the Rebel T3 to be a pretty limited body. A great solution would be a T6i and the Canon EF-S 17-55mm f/2.8 IS USM Lens. Most of the time lenses are where it's at. They are what make the picture. Not the camera.
"I could sell my in perfect condition T3 for 150-200" Yes, a good idea. Get somebody else started in the hobby. 
Also sell the lenses you have, "EFS 18-55mm 4.5, and an EFS 55-250mm", too.
Better camera deserves better lenses. Right?
Now about the 50mm f1.8. i wouldn't buy one. Primes offer little and are very specialized now. Zooms are nearly as sharp and far more versatile. The 50 does offer a little more than a stop in aperture. That's about it though.
Give the T6i and the Canon EF-S 17-55mm f/2.8 IS USM Lens a good look. Just a suggestion but I would get the battery grip with a T6i. It turns it into a totally different feel. Much better, IMHO, of course.
@jdundas wrote:Considering my very limited budget what would you think about me picking up a helios 135mm 2.8 for around $120-150? I also picked up a 50mm 1.8 yesterday which I am enjoying. Right now I can't drop $700 or more on a lense. If I were to buy a 70D it was going to be in the future..
What purpose is this "helios 135mm 2.8" going to serve? How good is that lens? Your 55-250 covers that focal length already.
The EF 55-250 f/4-5.6 IS II lens that I have is a pretty good lens for the price. It gets great bokeh. Here is a shot with your same lens, that just happens to have been set to 135mm.
Rebel T5, EF 55-250 f/4-5.6 IS II, 135mm, 1/250, f/5.6, ISO-200, "P" mode. This is a "practice" shot, for bokeh [and DOF].
You have just picked up a new(?) 50mm lens. I hope you have the EF 50mm f/1.8 STM, the one that has a metal connection to the camera, instead of the cheap black plastic. Learn to use that lens' wide aperture effectively, save your money.
Practice controlling the bokeh [depth of field], to produce shots like the one above. Both foregraound and background wild flowers are equally out of focus, with only the flowers at a mid-range distance in focus. I had to move to just the right distance, and focal length, to get that shot.
Remember, the more money you save now, the sooner that you can get that camera upgrade at some future date.
"... a matter of personal taste, than anything else?"
Yes sir, it is. And that, my friend, is the point to all photography. You just might make it yet! If you like it that is all that is important no matter what 'terms' are applied.
But, my deffinition of bokeh has more to do with specific "points' or highlights in an OOF background. The Christmas tree light example is one that is always passed around. Bokeh is mostly or largely controlled by the shape and number of aperture blades.
"Yes sir, it is. And that, my friend, is the point to all photography. You just might make it yet! If you like it that is all that is important no matter what 'terms' are applied. "
It was merely a test shot, a self-imposed homework assignment, if you will. I achieved everything that I wanted with the shot, as seen in the lower left and right corners. I was figuring out how to get nearby and more distant flowers equally OOF, while the mid-range wild flowers could be in focus. For that lens, it is a pretty good shot.
As far as bokeh goes, the more distant background greenery is my idea of bokeh, not the OOF flowers.
[EDIT] "Practice controlling the bokeh, to produce shots like the one above."
I suppose that I mispoke there. I should have said practice controlling the depth of field.
