No. Read in plain text is all or nothing. When its enabled, its just one quick click to switch messages to HTML. You could use VBA to convert messages to plain text and could restrict some senders, but its not an optimal solution - any message converted can't be converted back to html. Or, you could deliver all mail to the junk folder, except the mail that you want left in HTML - the junk folder is plain text always.
If you are doing this for security reasons, note that Outlook's reading pane is very safe and does not run active content.