Our house is never 21C 😂 unless it’s summer. Seems warm to me too. We have pjs (no vest) and a duvet.
That does seem a lot of layers for the room temperature. We just have long sleeved pyjamas and a duvet (sometimes with an extra blanket on top depending on how cold it is outside). His room is generally around 18-20c. X
Every child is different but all of those layers with that temp seems warm to me?! I thought 2.5 tog sleeping bags were for between 16 and 20°c. Is it just her hands that are cold? And not her neck, chest, back etc? If it's just her hands then the temp is probs fine. The reason for her waking up early could be the 2 yr sleep regression