I used to have a bunch of trouble with pads, but really it isn't all that difficult when you know what plugins do what and how to successfully combine them.
Generally for smooth trance pads I start with a moderate attack and a long relase on the volume and cutoff envelopes. Start off with two saw oscillators, one of them a higher octave but quieter, which you also should slightly detune. Use a lowpass, preferably 24db+ and don't let a lot of mid/high frequencies peek out. Next I add a very smooth chorus to the mid/lows and then a wider one to the mids. Reverb and delay are also key, and I put them last in the effect chain. Some people go heavy on flangers and phasers, but as a personal choice I use them very lightly for a tinge of movement.
There are countless formulas for making pads, but instead of looking to a new vst to solve your problems, utilize your basics first! The best creative work arises from limitations. ;)