I understand what you are saying, and some of it is IMO sound reasoning, but...
Williams and Hentges are likely to be back soon, but how far into the season do you really think TMac and Cookie will last? How many innings do you expect a starter to last with an elbow problem? We have two.
Brennans wRC+ is 87. His career number is 88. I expect him to be better, but its hardly like his present lack of production is unsustainable. Even more so with Freeman. His present wRC+ is 105, well above his career 87. While I'm high on both..esp Freeman...its not like they are underperformed what they've shown so far.
I think we are an above average team, but that comes with several major caveats, including having an upper level rotation that remains healthy and an elite pen over the course of 162 games...both of which I think are...uh...questionable.
We talk mostly about our offense. Is it really improved? Are the results, individually and as a team, sustainable?
None of it matters if the pitching blows out.
The Guardians are 4th in the majors in runs per game and nobody other than Kwan is performing OVER their career norms. OK, David Fry, but he's had just 35 AB's in 25 games.
By the way, Fry is 5-for-13 with 9 walks and 2 HBP against left-handed pitching. That's a .640 OBP! He won't keep that up.
Jose is well below his norms. Bo is hitting .186. It's not like we have five guys hitting at clearly unsustainable levels.
The question is whether we can continue to hit .315 with RISP. Probably not.
The stat I find interesting is the Guardians rank 4th in on-base percentage with runners on (.361) but just 23rd in on-base percentage with the bases empty (.293). They're well below average at getting the first runner on base, but once somebody is on they've been outstanding at getting more runners on and knocking them in. They've had a lot of mutliple run innings. Rick and Matt have commented on that.
So although they may not continue to hit .315 with RISP, I think they will improve at getting the first runner on base, which will create more opportunites to score. So it might be a wash. It will be interesting to continue to track this.
The Guardians are good at a lot of things and it's hard to say if they are sustainable because their schedule has been rather easy.
The Guardians are 4th in doubles. Probably sustainable because they make a lot of contact and have good overall speed.
They lead the majors in getting plunked. Very sustainable as long as Gimenez is playing.
They have the 5th fewest strikeouts. Sustainable due to excellent bat-to-ball skills. The Guardians rank 2nd in outside the zone contact percentage, meaning even when they chase bad pitches they foul them off (or sometimes make outs) more than all but one team.
They're 8th in stolen bases. Sustainable.
BABIP - 18th. It's not like they've been exceptionally lucky.
Sac flies - 2nd. Given their high contact rates probably sustainable.
Line drive percentage - 2nd. I don't know about this one.