If you are only going to perform one service or in a single work phase, you are likely to get bored and unchallenged unless it is something that truly fuels you. See if you can redress a balance between different ways of doing and thinking - a single afternoon of creative work may be enough to do that for you within your current job, you may want to try to get involved in new product development at your current company, do your own projects next to your current job, or you simply step back into industrial design which should realistically be possible since you already have a degree and some work experience. More important than being a good sketcher is being a good communicator and having good ideas and energy, the ways you bring that to others is up to you. Make an informed, critical and realistic choice and go for it!