Just get them all
I have an Arc, MIG, Spot and Gas welding machines/sets ... just missing out on the TIG.
I use the MIG for tacking and alot of panel work. It is fanstastic for installing a (butt welded) patch ... as you have a hand free. It is also good for welding the patch in ... just got to use multiple tacks. If you try and run a weld there will be too much heat and it will distort all over the place ... and pull the panel out of shape as the weld cools
I use gas when I can get to both sides of the panel and (after tacking with the mig) I fusion butt weld ... and hammer as required while cooling. I had stopped using gas for this, but it really is great.
I hardly ever use my Arc ... I used it to make the chassis jig and race car trailer, etc. but find the MIG is used for much of this too.
I also hardly ever use the Spot welder as it is very heavy and takes a long time per spot (being single phase) ... but I do use it ocassionally when I want to do a real spot.
I enjoy welding and it really is something that gives me a degree of self pride ... call me simple, but yep I get something out of it ... and confidence really helps the process.
Keep at it ... we can all get better, and all our Alfas benefit