Account-blowups usually happen due to one not having/taking one's SLs or risking too much money per trade, so I think developing a strong trading-discipline & having good money-management is more important to preventing account-blowups because without these fundamentals, one will continue to blow-up accounts irrespective of their size. In my opinion, capital-size should be based on the amount risked per trade, & as you might know, 1-2% (or less) per trade is most widely recommended. This ensures that when you have to take your SL according to your strategy, it's only a small amount of the total capital & therefore it's easier to accept that loss & move on whereas if it's a relatively large amount in relation to your account then it's that much harder to accept that loss & move on.
I don't know if this helps but just my two cents.