Thoughts on BUPA "Extra Care" health insurance to supplement other insurance?

Hi, anyone have any thoughts or experience with BUPA's "Extra Care" for supplementing a more solid health insurance?

My family has a rather expensive William Russell insurance. For myself and my wife (but not yet my children), there is an USD 10,000 deductible, which

halves the premium for us two, though it's still expensive. This means I self-insure for the first USD 10,000 of any illness, but now I'm thinking of a way to reduce the risk of this. Best would of course be to do away with the USD 10,000 deductible, but that will increase the WR cost for me alone by USD 1,000. A much cheaper option seems to be BUPA's extra care. This costs about 3,000 - 5,000 baht per year. I.e., about 1/8th of the WR extra cost.

The midlevel "Extra Care" has an " maximum aggregate limit of" 400,000B. I.e., about the same as my WR excess, though even BUPA "extra care" has a 20,000B deductible. So the first 20,000 I'd need to pay myself regardless. I'd prefer not too pay this either of course, if there was another more fitting insurance, but I'm not too worried about the 20,000B. I am much more worried about USD 10,000 per family member.

I have contacted WR, and they afaik have no problems with another insurer covering the WR USD 10,000 deductible. It would to me not make any sense that this should be a problem for them either.

Basically I would depend on the expensive WR insurance for the real catastrophe, but would hope the cheaper BUPA "extra care" would cover most of my WR deductible and some not-so-serious stuff.

Anyone with any intelligent thoughts or experience regarding this?