If he's willing to stay here, I'd certainly re-sign McElhinney. I wouldn't go into the season with Ned projected as part of the tandem. If he takes the job in camp, McElhinney would be easy enough to deal.
I think Mrazek has been slightly better than his numbers, and I do think he's been an upgrade over the Ward of recent years, but I would definitely look to upgrade him if possible. I do like the idea of Talbot, and I don't think he'd be any worse than Mrazek here, but he could end up better. I would likely stay away from Lehner as he will probably look to get (over)paid. If you could somehow get him cheap, go for it, but in that case, I don't see why he wouldn't stick with the Isles. I'm not opposed to bringing back Mrazek, but it'd have to be at a pretty cheap contract. Collin Delia, Alex Stalock, and Casey DeSmith are all goalies that have similar-ish or better numbers currently or in the recent past that signed super cheap (expansion draft related) deals for 3 years. The only goalie of that ilk that got paid recently was Koskinen, and that was a huge mistake. If Mrazek wants that, he can play hide and go **** himself.