It is such a personal choice. Do you even like Spain? Where in Spain would it be?
We are in Spain, we were here with work..We left, came back, and may have to leave again. It is hard because it kind of is home, but not really...They seem to be introducing a digital nomad visa that is looking ok (if you don't have a EU passport).
There are many positives - private health insurance is not expensive and much better than what I was offered in UK.
Schooling - many regions (if not all) speak two languages, so state schooling is not in Spanish but a regional language. We all started our kids in state schools but many struggled and ended up in international schools, or private Spanish schools (where the local language is a bit less represented). Depending on where you go schools can be ok or not so much.
*They are not all sponges and not all of them will be fluent in 6 months - I find it really important to say this because my child really suffered and couldn't cope with the demand of three languages at such a young age...It took them a long time to recover their confidence.
The weather - is great but also brutal. July and August, even September this year were so hot and you are so limited with what you can do. Out with the dog at 6am every day gets a bit tiring.. Ditto with going to the beach...
Employment - the average wage is not really high. There are many jobs you couldn't do unless you are fluent in two languages.
Taxes - are high.
My negative bias may be coming from the area where we are, it really isn't a perfect fit for me and we may move somewhere else when the child is finished schooling, however, it is still something to think about.