Probably will depend on how much £/€ you are willing to spend! An upgrade to v13 shouldn’t cost too much and will probably give you many benefits. I suspect what you have is going to do most of what you should need. After Premier Elements you are probably going to have to spend quite a bit to get anything better. You are probably going to have to go to full fat Premiere or something like Sony Vegas. An other alternative is Sony Movie Studio 13 Platinum – never tried it but I would suspect that it would be similar to what you already have.
It may be worth buying a decent book on Elements as it is already a very capable piece of software and a lot of options are similar to the full fat version. There are also plenty of video tutorials out there which are free.
When you say more effects, what do you mean? Sometimes subtler effects are better than the whizz bang stuff. A good idea is to watch TV shows and documentaries and see how they use transitions and effects. In many respects it is like when word processors first appeared. There was a huge choice of fonts and everybody tried to use all of them in a single document. It is possibly best to limit the use of effects within a video.
As with most photography, try and capture an image or video that is as near as you can to what you want at the time. For example, check the exposure and white balance settings before you shoot. Obviously this depends on you having enough time do that. Try and avoid digital zooms generally and also try to not zoom too much whilst recording. Let the subject do the movement - try and not follow it too much. Slow, short pans are ideal.
If I’m hand holding a camera for video this is what I try and do… First, hold the camera lower with both hands so you can wedge your elbows into your body. Most times, using the camera single handed can cause wobble. Second, if you are going to do a pan aim yourself towards the middle of the shot. Then, turn at the waist keeping your legs in the same position to the start point. Start recording and slowly move at your waist towards the end point.
Software video stabilisation can work but you do start to loose quality. If you film in 2k or better for example, that gives you a lot of room to produce a decent HD clip. Having strong and stable camera mounts helps to avoid wobble and shake. Using a gimbal can help with hand-held camera shake but with practice you can get smooth and pretty stable video. YouTube has quite a lot of home made video mounts that can help with camera stabilisation.
What do I use?
I use Final Cut Pro X for video editing running on an i7 Mac Mini server. Does most things that Premiere does but I find it easier to use. Special effects can really take a lot of processing. Colour balancing was the only tweak I made to the Paint Drying video. Though I used a light source there was also daylight (which was also changing throughout). No colour balance took about 2 hours to render, with colour balance it too about 8 hours to render! Other than buying a 16 core 64GB Mac Pro it will take a while to do more complicated stuff. For some simple videos I use Windows Movie Maker and for others I use iMovie on iPad/iPhone/Mac. Easy and quick to use.