I just did the mainboard on a 2012 MBA for a friend. The board itself was under $200 on EBay and took about 15 minutes to replace.
I’ve never seen the innards of the 2010 version, so I cannot speak to ease of replacement, but looks like the logic boards sell for $150-200.
You can’t get a new Macbook for that price, and it’s less money in Chinese polluters’ and Apple pockets, so I’d say go for it.
The other option is to bake the logic board. That’s right. Heat an oven to 375F, remove any foam parts from the board, bake it on standoffs in a preheated baking pan for 8 minutes, then let it sit till it’s cold. This reflows the solder on the board and sometimes fixes issues.
