Underboss
We have both a fiesta of the same generation as yours and a Focus ST estate.
The pointers you've been given about being careful with trim level and in particular suspension / wheel size are fair ones as I would say our fiesta on 16" wheels rides better than my ST. Not sure that should be a surprise but if you buy a car the same size as the focus with suspension to mimic it, but without the power it'll get pretty old pretty quickly.
I don't think there is such a thing as a bad car in this segment really, if I were you I'd go and look at a well specced example of absolutely everything from roughly the age you've mentioned including the Kia / Hyundai's etc. My neighbour has a new shape i30 and it's a nice little car.
If the badge matters more I'd personally go for a 3 series over a 1 (I know you say they seem big but have a look round, they aren't big cars) despite the similar interior. An IS300h may also be worth looking at, don't judge the interior on some autotrader photos they "feel" far better in person albeit you'd be buying one because it's a Lexus and will probably be reliable.....the BMW is a better looking car inside and tech wise. Probably closely followed by the Golf. Leons are a smart looking car externally, but the interior looks significantly cheaper than the sister car.
The Lexus' look much better than the BMWs imo. Modern BMWs are fugly :/
But yea with Lexus you are paying for robust engineering over gimmicks, they are tanks and that's why people buy them. Also Lexus dealers are nice to deal with which is a bonus, if there is an issue they just sort it out without an argument.