Stacking
I know many people who say they don't have space for dryer, and just forget to stack them.
But a tumble dryer isn't matchable in results by any form of hang drying.
Softer, less creased, quicker.
I live near the sea and if you hang dry here, you need a huge space and constant ventilation, otherwise you will have mold issues.
I have some granulat based dehumidifiers in my kitchen and bedroom to keep moisture levels even. They wouldn't be viable if I used them as clothes drying support.
I tumble dry everything and so do both of my flatmates, but we still use an acceptable amount of power.
An A++ dryer for a single person should be enough in terms of efficiency and can be had pretty cheap.
A+++ of course is better, but a bit more pricey.
If a washer dryer combo is the way to go, many of those sadly use a lot of energy, a lot of water for drying and are anything but safe for everything.
The only reasonable washer dryer combo with a heat pump is the AEG ÖkoKombi, but it is on the more expensive, complicated and failure prone machines.
But it performs pretty OK apparently for a combo.
Pricing is comparable to a mid-line washer and heat pump dryer seperartly.
But I would get an extended warranty for sure with that one.