For future reference, I really think the best way to have a less touristy experience is to stay somewhere long enough to see the key local sights and have time left over for aimless wandering in attractive neighborhoods not immediately surrounding those sights. Or you can go to cities you hadn't head of until you read a comprehensive guidebook. Your stops in Seville, Madrid and Barcelona are extremely short given their attractions--fewer days than I'd recommend for someone just interested in tourist highlights. To have the sort of experience you want, I think you're going to need to skip some highlights.
For the best advice on what you probably shouldn't miss, you'll need to tell us what sort of things you're interested in--art (what periods?), history (what periods?), architecture (older or funky?), etc. I think you'll probably find food tours available in several of your cities.
According to Wikipedia, these are the average high and low temperatures for February in your cities; since you're visiting in the first half of the month, your averages may well be a bit lower. Keep in mind that traditional Spanish dinner hours are between 10 PM and midnight, so the daily low temperatures are of more than minor interest unless you intend to dine on tapas or seek out restaurants opening quite early to serve tourists.
Madrid: 53.6F / 38.7F
Seville: 64.6F / 44.6F
Malaga: 63.9F / 46.8F
Alicante: 63.7F / 44.8F
Barcelona: 60.1F / 48.7F
Those temperatures (which don't indicate shorts weather to me, but I'm cold-natured) are from Wikipedia and are based on a time period that cuts off in 2010; things may have changed over the last twelve years. For better data to help with your packing, I'd recommend checking the website timeanddate.com for actual, historical, day-by-day weather data in recent years. Here's a link for Madrid (which could be quite chilly indeed): Madrid weather February 2022. You can use the pull-down box just above the graph at the right to check other recent years (highly recommended). Use the search box near the top to check your other destinations.