If the snapdragons were mine and they looked good, I'd trim them a bit and keep them. Let us know what you do and how it works out.

I just tossed a big pot of leggy, twiggy, sticky, but-still-blooming petunias as they were a disaster, LOL. I feel bad for a second, but then look forward to refreshing the soil, and planting something new.

My go-to plant for flowers is annual Vinca. It does great for me from mid-spring through mid-autumn, although I know some folks have trouble with it getting wilt when over-watered. I've never had an issue. I also grow a lot of zinnias from seed and they love the heat as long as they get watered. Celosia and gomphrena are good for summer too, and don't forget things like lantana and tropical hibiscus which love the summer here and can be kept year to year if desired or discarded in late autumn.

I do cut back a bit on flowery plants in containers in summer, and just stick to a pot or three of vincas or portulaca ("moss rose" another one that loves it here in summer); in the ground for annuals, I do zinnias and vincas.

Looking forward to your updates, plus what other folks think about your snapdragons and their favorites for summer annuals too.

Take care all and happy gardening!
Grant

Here is a link that might be useful: Pics from my garden April 2012