Re husbands staying in labour. There are two stages to talk about here:
1. Before you are admitted to the delivery room. Here, you will be in a general ward with other labouring women and officially your husband will only be able to visit during normal visiting hours. However, I have heard of lots of husbands persuading the staff to let them stay with a curtain drawn around the bed (you will not be able to get approval for this in advance though, and it's at the discretion of the staff who happen to be on duty). Also, you can minimise the chance of being a long time in labour by yourself by waiting longer at home before going to hospital. This has the advantage of your labour hopefully progressing faster in the relaxed surroundings of your own home. In some countries like the UK there is a shortage of beds in public hospitals (this doesn't seem to be the case at QMH maternity ward) and they will send you home until you are at an advanced stage anyway! Some people in HK hire a midwife to look after them at home if they are nervous about something going wrong with this plan.
2. After you are admitted to the delivery room, which is when you are more than 3 or 5cm dilated (it's not an exact science) and there is a room available, husbands are allowed to stay with you the whole time, unless you need to have an emergency c-section.
Re spending time with you and baby in the few days after the birth. I was in QMH for just over 48 hours and I must say I was glad not to have more visitors! If everybody had more visitors it would make the ward very noisy, for a start, plus I was too tired to make conversation. Most babies sleep a lot during this time, recovering from the exhaustion of the birth. I know from the father's point of view 48 hours can be a long time if you can't think of anything else but the baby, but not a lot happens compared to when you get home. From a selfish point of view, I also enjoyed the time by myself to bond with the baby and learn to breastfeed, without my husband fussing around, worrying whether she was still breathing or my breast might be suffocating her (which is what happened when we got home), and after 9 months of pregnancy surely what suits the mother counts for something!
Re holding baby ASAP after birth. If you write a "birth plan" in advance, this is usually possible unless there is a medical emergency. I did request to hold my baby straightaway, but in the end it was a couple of minutes while they checked her vital functions (in the same room) before me and my husband got to hold her. I have heard of others holding their babies more immediately if they made that wish explicit in advance. Fathers can even cut the cord! (Again, need to express this wish in advance.) If you are intending to breastfeed then QMH will support that by encouraging the baby to go on the breast as soon as possible after the birth, and during that time we were left alone by the nursing staff for quite a while, maybe half an hour, before I was moved to the ward.