There is no reason to anticipate revolvers being affected by most proposed legislation. If any capacity bans go through, it will be your magazines that go up in price, so trading a G19 for a revolver due to concerns about the political climate seems silly.
Also, a G19/26 combo is a good thing. You can use the 19 mags as spares when you carry the 26; manual of arms is consistent between the two; holsters and mag pouches can be relatively interchangeable.
Save your money, and just buy a revolver later.
If you are worried about possible legislation, don't panic buy or trade. Contact your reps, express your pro-gun views, and if you want to spend extra, donate to proven RKBA organizations.
None of the trades you listed make as much sense as taking those actions.