I'd recommend against blower style coolers like the ones you listed. They run hotter than the open air coolers on OEM cards, which could cause thermal throttling specially with such a powerful GPU.
More to the point, if you look at the review of the RVZ-02 that DonkeyOatie posted, they used an open air style 980 Ti and still got excellent temps for what is essentially an SFF case, so I wouldn't worry too much.
Since you seem a bit undecided on the case, here are the main options you have:
The basic ITX case. It is literally an ATX case shrunken down to ITX proportions, so it has the best cooling and will be the easiest to work on. Is also the biggest, however.
The square form factor. Less than half the height of the basic ITX design above, slightly narrower and has less depth. Basically smaller in every way. Somewhat worse airflow due to the congested interior, but still most cases can use low profile air coolers with good results. Both this and and the case style above support watercooling. Although some square cases like the Silverstone Sugo SG13 can only
practically (It is possible to fit an air cooler in it, but the clearance is extremely small.) be used with a water cooler, there are many other great cases like the Fractal Desin Node 304 and the Raijintek Metis that support air cooling with great results.
The HTPC form factor. Originally meant for use as home theatre PCs, this slim form factor has now gained traction in the custom building community since it started supporting higher end hardware. Significantly thinner, but around the same depth as the square form factors. Height is in between the top two styles. This style of case won't support watercooling, but generally due to the clever use of individual air channels cooling is well within acceptable levels. You will, however, be extremely limited in your choice of CPU coolers, and PSUs as well. Not that good for upgradability, but if you plan to hang on to the system it should be fine.
Obviously, there are exceptions to the rule, so not all ITX cases will fit exactly into a category. This does represent the three main types of cases available, however, so take your pick

.
Personally, I'd go with a square form factor case, since it is a good compromise between portability and ease of installation / upgradability. For reference, a normal square form factor case like the Fractal Design Node 304 is about the length of your average subwoofer, at about half the height and slightly more wide.