I wouldn't call the T6 much of an upgrade from T2i.
T2i was the top-of-the-line Rebel model in its day... 18MP and with features like an articulated LCD screen.
T6 is one of the most entry-level Rebel model currently in production.... also 18MP, only a fixed LCD screen, but with WiFi.
A Rebel T6i or T6s would be much more in line as an upgrade. A slighlty older T5i would be, too (and has a simpler auto focus system that would be more familiar to you... but still is upgraded compared to T2i).
Any of these models, you might take a look at the Canon USA online store's refurbished camera offers. They've had a killer deal on T6i recently, if I recall correctly. Stock comes and goes there, so you might have to be patient and wait until what your want comes in stock.
For brand new, USA warranted (not grey market) at B&H PHoto in NY, I see there also is a $200 instant rebate now for T6i with 18-55mm STM lens and $350 instant rebate for T6i with both 18-55mm and 55-250mm lenses. There are some discounts on the more expensive T6s, too.
Most often those Rebel series cameras come with kit lenses. Usually it's the EF-S 18-55mm IS STM, and sometimes also the EF-S 55-250mm IS STM. These are good deals too, when bought in kit like this... but you should price things separately to see for yourself.
I would NOT recommend the Tamron 16-300mm you're considering. For one, third party lenses aren't guaranteed to work on future Canon cameras. They may or may not.
Also, that type of lens is very slow and a terrible choice for available light, indoor shooting. For that you either need a much more expensive and high performance zoom such as an EF-S 17-55mm f2.8 IS USM or one or two even faster prime lenses such as EF 50/1.8 STM or EF 50/1.4 USM. By "fast" I'm refering to the larger aperture of these lenses. That Tamron lens is f/3.5 at the wide end and only f/6.3 at the telephoto end of its zoom. This means it admits far less light than either the f/2.8, f/1.8 or f/1.4 lenses. For example, f/1.4 admits two stops more or 4X as much light as f/2.8... or over four stops more or 16X as much light as that Tamron at f/6.3!
In addition, that Tamron lens is an "entry level" model with "piezo" motor driven auto focus. I haven't used it buy imagine that's pretty similar to Canon's micro motor lenses, which are the slowest focusing of all. STM are faster and USM are even faster yet.
And, quite honestly, while a 20X zoom like that 16-300mm might be convenient, I'm not a fan of "do everything" zooms. In my experience, they don't do anything particularly well. Not knocking Tamron (in fact I use two of their more pro-oriented "SP" lenses in my daily shooter kit and have used many others in the past). But this type of lens just doesn't make sense to me. The whole idea of an interchangeable lens DSLR is to be able to adapt the camera for use in different situations. Fitting one with a 20X zoom just sort of seems counter-productive.
You mention shooting video and if you want to be able to autofocus that, Canon's STM (stepper motor) lenses are preferable for that (except for a few recently very released "Nano" USM lenses). STM isn't quite as fast focusing as USM, but it's quieter and smoother operating for video work.
The Rebel T6i and T6s are very similar cameras with a fairly advanced AF system (19-points, all "cross type", similar to what was used in 70D and in turn that camera inherited a somewhat simplified version of the AF in the original 7D). They are 24MP models three or four generations newer than your T2i and with a lot of improvements compared to the older camera. The T6s has some additional displays and controls, unique for a Rebel series model (sort of borrowed from 70D/80D). It also has some video-related enhancements, so might be of interest to you.
A new lens that Canon introduced alongside the 80D also might interest you. The EF-S 18-135mm IS USM uses a new "Nano" form of USM "ultrasonic" focus motore that is faster than STM and optimized for use shooting video. (Canon has since introduced two more Nano USM lenses: 24-105L IS USM II and EF 70-300 IS USM II.)
Something unique to the EF-S 18-135mm USM is that a matching PZ-E1 "power zoom" module is being offered for use with it. This is another thing a videographer might find interesting and helpful. This module only works with this lens, AFAIK.
Hope this helps!
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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2) some other cameras, various lenses & accessories
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