As a US citizen, is it easier to petition for my spouse from his TPS status or an F-1 status?

It does not matter really in which order, separately or together you will be sponsoring your family member. Your only concern can be an affidavit of support. You might have to have a joint sponsor.

Although significantly more information is needed in order to provide a legal analysis, in general there is no advantage for a U.S. citizen to wait until after sponsoring parents for immigration benefits before sponsoring a spouse for immigration benefits. If you may not have sufficient documentable income to meet the Affidavit of Support requirements for a "family size" that includes both parents and a spouse, then it may be necessary to have a joint sponsor. Generally a joint sponsor may be any U.S. citizen or Permanent Resident who has sufficient documentable income and who is willing to assume the responsibilities contemplated in the Affidavit of Support. Of course, there are many other details that determine immigration eligibility. It would be wise for you, your parents and your fiance to consult with an immigration attorney who, after learning all of the relevant information, could advise about eligibilities, options and strategies to attain your goals, and who then could offer legal representation in the often complex application process.