Yeah, I agree with the ladies that the first thing I would do is update the bras and undies, and jeans if you wear them regularly. Also, the hair and glasses if you wear them/haven't updated in a while. Otherwise trendy things will look "off" next to dated hair or glasses and the fit of clothes can be affected by bras and undies.
However, from there I think everyone builds a wardrobe differently. If it seems overwhelming to "stock up on basics", then maybe you should take it slowly and go one outfit at a time. If you see a trend or piece you like that you think you could wear in your climate and with your lifestyle, start there!
For example, if you find a floaty blouse you think will work then you can search out the basics that go with it to make an outfit. Maybe you need a slim jean skirt and some nice wedge sandals, and a great bag. Maybe you already have some earrings or a watch that will look great. Then you have one complete new outfit. From there you can take the jean skirt and find a striped T, or a more structured woven top that also looks good with it. Maybe the wedges still work, or maybe you need new shoes or different accessories to make it into a great outfit. Let's say you buy some great flats that would also look good with a sundress or clamdiggers. You can look for a great dress that participates in a trend too.
Pretty soon you have 6 or 7 great everyday outfits. You can determine how many you need and how many items are "trendy"--- even if your ikat blouse doesn't float your boat next year, you still have the clamdiggers, denim skirt, wedges, striped T, ect. Maybe at this point you decide you want a few more everyday things, otherwise you might decide that you are comfortable with what you have to start, and you want to live with these clothes and see how it works out for awhile. Otherwise, maybe you need to work on other "capsules" like making sure you have something appropriate to wear to things that come up frequently, like funerals, weddings, church, dates, whatever comes up in your life.
I personally don't think there is any problems with trendy items, so long as you aren't trying to build a wardrobe of all the fun new things only, with nothing that will stick around for more than one season, or nothing to ground your "fun" pieces. Or trying to update outdated things that aren't flattering or appropriate by adding a new top or two. I think any of these approaches often lead to feeling like a failure. Nothing is going to look right without a good bra, and good workhorse pieces to pair with it.
