I used to have the smaller scale NECA (7-inches?) ALIEN Big Chap figure. I gave up trying to pose him standing with his arms outstretched (Lambert reveal), and tried the 'crab-walk' pose instead. That didn't work either.
The larger 22-inches (2015) Big Chap figure (with the ratcheted legs) is an improvement.
Still, I have mine inside a display cabinet just large enough to contain the figure in a standing (again, slightly hunched, arms outstretched) pose, up against the back wall.
Just got to keep an eye on him during the summer months, as his plastic legs start to soften and he shifts position (happened last year).
* I don't use stands.