Welcome to the forums!
Both chronic hypertension that is requiring three medications to control and underlying kidney disease will put you at very high risk of recurrent preeclampsia and/or HELLP syndrome, simply because your baseline inflammation levels are likely to be quite high. Superimposed PE and HELLP appear on top of those underlying conditions
, probably because the body cannot tolerate the additional inflammation caused by a foreign organ (the placenta.) Technically, inflammation means an elevated innate immune response to *something* - and on top of that you'd add the response to the pregnancy itself.
So the thing to do differently would be to get those conditions as well-controlled as possible before TTC. Some women see significant improvement in hypertension with weight loss or exercise or diet changes, and you'd have to see how your body responded with a personal trial. Some women have hyperfiltrating kidneys and benefit from some treatment with an ACE inhibitor (which isn't okay during pregnancy, but can improve kidney function outside pregnancy.) These are all questions for your doc, so I agree that I'd want a pre-conception consult with a maternal-fetal medicine specialist who's in the habit of managing these medically complex pregnancies.
We've had quite a few posters with kidney disease and while they usually do go on to develop preeclampsia in subsequent pregnancies, the timing of onset varies for them. That's probably caused by differences in the genetics driving the pregnancies. Every pregnancy is different.
Hope this helps, and welcome again!