How can I more aptly describe acceptable laziness?

How about "satisficing"? It comes from "satisfice":

Satisfice verb Decide on and pursue a course of action that will satisfy the minimum requirements necessary to achieve a particular goal.

From Aziz Ansari's Modern Romance:

According to [the scholar Herbert] Simon, people can be maximizers and satisficers in different contexts. For example, when it comes to, let's say, tacos, I'm a maximizer. I'll do a rigorous amount of research to make sure I'm getting the best taco I can find, because for me there is a huge difference in the taco experience. A satisficer will just get tacos wherever they see a decent taco stand and call it a day. I hate getting tacos with these people. Enjoy your nasty tacos, losers.

Since you tagged this both single word and phrase request, I assume you are okay with either suggestion. Therefore, it seems you are trying to take the path of least resistance. (Wikipedia)(Idioms - Free Dictionary)

The idiom implies there is a goal or task that must be accomplished, and multiple choices for how to do it, one of which is simpler, shorter, easier, or similar. Other paths may accomplish more than is needed or leave less problems for the future, but at the expense of greater effort now.

In your examples:

I'm going to buy a new shirt from the clothing store across the way because I spilled some tea on this one; it's taking the path of least resistance and ideally I'd go home and change, but I have an important meeting in a few hours and I don't want to spend time stressing about being in too many different places at once.

And:

Well, I'm trying to take the path of least resistance, so why don't I just set that client to run on Wednesdays rather than Tuesdays, and it will just run like usual tonight? It's not urgent, right?

For the first sentence, you could use "sub-optimal" or "good enough".

For the second sentence, you could use "pragmatic" or "efficient".