Almost everybody will buy a buggy/lighter, non-reversible pushchair later on. It is so because a reversible stroller is always heavier, bulkier and less spacious in the seat - read more HERE. However, nobody will make you buy a light, compact pushchair or an umbrella stroller if you'll be happy with your larger pram, and if your child won't be too large, it might even serve you well until the end of strolling days.
About the Balios S, it is certainly much more suitable from birth, than the lighter, rattly Eezy S-Twist line. Those should be considered a second, occasional, lightweight option, a tiny baby will be shaken and not so protected there. I would only buy an Eezy S-Twist from birth as an only stroller if I had no other option, e.g. if our lift was tiny or non-existent, and if I needed to carry my stroller upstairs every single day.
Don't worry about later. If you won't need something lighter, you'll simply use your Balios S. OR get a lighter model, like a Cybex Mios, if you absolutely need a stroller that will last you until the end. But I see no problem even selling a bulkier pram after 1.5-2 years of use, getting part of your money back, and getting a lighter model. Really, take it easy, go for what is comfortable for a 3 kg baby, and the future will resolve itself when it's time. You will see your needs changing as the baby is going to grow.