Using Rokinon 14mm or Tamaron 17-50mm as a general purpose lense (APS-C)?

I dropped my Sigma 18-250mm in the river and now looking for ways to replace it. I am using T4i, and have,

1. Canon 50mm f/1.8
2. Canon 75-300 (Garbage w/o IS :/)

I use the camera mainly on my trips to collect memories much more than to have great professional photos, but I do try to get the best shots I can. I mostly take landscapes, and some macros of flowers etc. and also wildlife. The Sigma 18-250 was quite a good lens that covered most of the range I needed, and quality was better than the Canon 18-55. However, I would like to get a lens with better quality if possible. Here are a list of concerns,

1. I have, more than a few times wished I had a wider lens than 18mm (~29mm? APS-C), and I do like to capture a lot of landscapes.

2. I barely used the range above 20mm on my 18-55mm.

3. I hate changing lenses and usually carry another camera with my girlfriend who can mount a telephoto lens on hers.

4. I don't want to spend more than ~500$

5. I use lightroom anyway, so not too concerned about vignetting/distortion/aberration as long as it can be corrected.

6. I would love to upgrade to a full-body later, and while it's a minor concern, would be nice to have one that fits well there as well.

7. I am a little worried about manual focus only, and wonder how hard would it be to get a good shot without live-view (Bat life is very important too, so barely use live-view).

8. It would be nice to have filter threads, and the rokinon doesn't have them.

9. Apparently you can get a focus confirmation chip and attach it to the Rokinon, which might be a nice addition..!

Sorry for super unorganized question. I have been researching for a while and still can't decide. I would assume the 14mm prime would have much better image quality, and is only 300$. On the otherhand, 17-50mm might have less distortion, and might be a better general purpose lense for 500$. Please feel free to edit the question to make it more coherent.

[Tomaron 17-50mm f/2.8 XR Di II LD](http://www.bhphotovideo.com/c/product/423714-REG/Tamron_AF016C700_17_50mm_f_2_8_XR_Di.html)

[Rokinon 14mm IF](http://www.bhphotovideo.com/c/product/769532-REG/Rokinon_FE14M_C_14mm_Ultra_Wide_Angle_f_2_8.html/prm/alsVwDtl)

Also, [Tokina 11-16mm AT-X Pro DX II](http://www.bhphotovideo.com/c/product/882235-REG/Tokina_atx116prodxc_ii_AT_X_116_PRO_DX_II.html)