I have no idea of the wieght of the rims you show in the photo.

R-Spec tyres come in a range of three compounds to suit the motor sport application and/or you budget.
Soft : heats up quickly and is used for hill climbs, gymkhanas and one lap screamers to set fastest grid time. Wears very quickly and goes off just as fast when the operating temperature is exceeded.
Mediums : Takes about a lap on the track to come to operating temperature and is probably the most widely used compound for track days. Wear rate depends on manufacturer but generally you get a season (8 – 10 track days) out of them on an MX-5. You wouldn’t get enough heat in them initially for gymkhanas.
Hards : Takes around two laps to get to temperature. Used mainly in endurance racing or where you do sessions where the mediums start going off as the lap numbers build.
Probably last twice as long as the mediums but slower lap times using this tyre. Again, you wouldn’t get enough heat in them at any stage in a gymkhana.
Using Softs would give you a lot more grip than the KU36’s but then you need to consider your budget. R-Specs will set you back $325+ each.