I think it depends what timeless means to you! I have a pair of black Closed pedal pushers that are my go to. They’re straight, they fit so well, and I always have them tucked into my boots, so I don’t mind the bit of ankle showing. I also have a skinny pair of jeans from them that fit brilliantly. They’re the best denim I’ve ever owned! Pricey but I buy mine second-hand online. Other good ones are AYR and Paige, but both better for skinnies. My friend loves the Perfect Vintage Jeans from Madewell, and they’re a nice, straighter cut, but I will say I adored Madewell jeans 10 years ago, and have some from that time in good condition, but everything I’ve bought from them in the last 3-4 years has lasted less than a year, so not worth it for me anymore.
For boots, everyone where I live has these, but I can highly recommend Blundstone Chelsea boots. I bought mine in 2020 so I could go for impromptu hikes if I needed to extend my lockdown walks (I live in an area with easy hiking access from the city) and I walk 5-6 miles a day, where them everyday, and I just had to resole them for the first time. They still look amazing too. I have the ones with more of a heel, a bit different than the flat Chelseas everyone has, and I love them. Otherwise, Repetto boots are my go to city boots, mine have lasted a decade, but they are pricey. They do not do Black Friday but they will go on sale in January when the French sale is on!
Hope that helps with either decision!