Hello,
1) We have fixed issue with the double h1 tag on the single product page, also we have fixed the double title issue.
2) h2 tags that you mentioned (description, product information) are default WooCommerce content http://prntscr.com/l0vxcp So, contact WC plugin support if you want to use another tag for these titles.
3) So, do you want to remove title in the breadcrumbs or in the post content http://prntscr.com/l0w26q ?
Regards