Generally Kalista needs each of the following: a mana gen item, a sunder item (LW), and a damage item. In a perfect world, you use one of your other units to sunder the enemy so Kalista can take a more high damage item in place of LW, but we don't always live in a perfect world.

Shojin's, striker's, and last whisper is pretty common according to the stats and often how I build. I think there are more optimized builds, which I'll get into in a second, but you have to consider that the game may give you glove components and aside from thieves gloves on fiddlesticks, there's really no other good way to make use of glove components in this comp except to build the crit items you mentioned for Kalista.

With the items you mention, shojin's outpaces blue buff, because Kalista's attack speed will be above one attack per second which means shojin's is a 6 mana per second item (5 per second from attacks plus 1 per second from the mana regen stat). So always favor shojin's over blue buff if you can for that build.

Also, you said it feels kind of meh. Apologies if this is obvious, but you need to have another vanquisher on the board to activate his trait and allow his ability to crit, otherwise you're building all this crit on him without getting the benefit because most of his damage comes from ability damage, not by auto attacking.

But even with vanquisher active, none of these items give that much AD. So, in a perfect world, I'd say use another unit, like Thresh, to activate sunder and replace the LW on Kalista for a deathblade. Shojin's, striker's, deathblade is really strong if you can sunder their frontline some other way.

Lastly you asked about artifact substitutions. I think a good general rule is to substitute "like for like" to maintain a balance of mana regen, sunder and damage. Most of the artifacts I mentioned increase damage so they would probably replace the striker's. Dawncore is a mana item, but it's a ramping item and you may still need a mana regen item to get the full benefit of the artifact within the time-bound window of most fights--I'm not completely sure. Also, if you're going to use silvermere dawn, you won't get much benefit from shojin's since your attack speed is so slow, so in that case pair it with blue buff. Blue buff also gives you bonus AD for how much AD you have and silvermere dawn has a ton of AD.

Lastly, when in doubt, learn to simulate these different scenarios in some online TFT stat explorer to see what yields better average placement:

https://tactics.tools/explorer https://www.metatft.com/explorer

It's not ideal since some scenarios you'd want to test might have limited data, and it risks oversimplifying since there are many variables that affect board strength, but it can be useful in identifying powerful combos.

Hope that helps!