Cool! Give a try. At 50kHz even the effect of leakage will be reduced.
And by the way adding a capacitor automatically nullifies the leakage reactance, if chosen correctly.
But I didn't quite get the idea of a series capacitor in the primary. Sounds cool theoretically, but do you really want to place a 30V 200A capacitor. Have you already found out which type of capacitors you wanna use?
At 50kHz the capacitive reactance would be 3.3 ohm per uF. When referred to the secondary, this translates to 3.3*36 = 120 ohm per uF. since you have three in series, you get a total of 360 ohms per uF
Your leakage will be in the range of 20 ohm to 50 ohm. So you need to get the capacitive reactance down to approx 20 to 50 ohm. That means a capacitance of approx 15 uF. Do you really want to use 15uF 200A capacitors!!? (Expect nothing cheap)
Electrolytic type is out of question due to high dissipation factor (typically about 5%)
X7R ceramic is also not impressive. (DF = 2% @ 50kHz)
C0G ceramic may work (DF = 0.07% @ 50kHZ). But what about the current rating?
Polypropylene film may work (DF = 0.1% @ 50kHz) Costs about Rs 25/- (0.4$ on Mouser) for a 3.3uF capacitor with current rating of approx 5A RMS.
I am also designing a similar X-mer with current rating approx 100A. Please keep sharing your experiences.