...is minting in the Terminal the only option?
Yes, right now the terminal is the only first party option.
As Marek pointed out, the community may have other ways. https://satran004.medium.com/cardano-client-lib-minting-a-new-native-token-in-java-part-iii-1a94a21cfeeb looks like a good tutorial if you're in the Java programming ecosystem.
If you are not a programmer or terminal guru, I'm pretty sure a web version and/or Daedalus version is mostly likely in the works. The Daedalus version will supposedly allow you to do some ongoing "management" tasks of your minted tokens.
I'm pretty sure they demoed a web page for minting Native Tokens on one of the monthly updates. Charles in one of his AMA also said he wanted to bring that management to both the web, then eventually Daedalus.
I was wondering if Marlowe Run has the feature to mint NFTs...
No, no minting functionality. That tool is specifically for creating smart contracts.