Hi Eva,
To answer your qns:
1) is having rom date being choose base on bazi as important as that with the actual date customary wedding? or not so much important for rom dates to be selected base on tong shu?
Yes, selecting of dates for ROM using Bazi is VERY important. In fact, ROM is more important than AD. There is always this misconcpetion that AD is more important. This is only true if you do AD and ROM on the same day. In the olden days, there is no such thing as ROM. Everything is done on the AD day. Hence that day is very important. Now, we have ROM. And ROM is the day both of you become legally and officially husband and wife. The AD date is just for tea ceremony and banquet. Hence, ROM will be the more important one. A good day and also a good timing to sign the ROM papers is very important.
2) my partner and i are considering to rom in 2010 before the tiger year. many have said that tiger year is not so much advisable. likely rom date to be 31 jan 2010 for the following horoscope:
31 Jan is a general good day and doesn't clash to any of you (clash to Pig).
May i ask what is it that you've heard that says that Tiger yr is not good for marriage? I want to know what you've heard coz there are 1001 stories about how bad Tiger yr is. At least i can answer directly towards your doubts in mind
3.) do we need to consider siblings horoscope as well for rom date? or even actual day customary marriage?
The answer is NO. Only both of you and your parents needs to be taken care of. Siblings and grandparents need not be considered.
There are only 12 animals signs. If both of you, plus your parents, plus let's say you come from a big family with 6 siblings, and all of you have different animal signs, then you don't need to get married forever coz every sign clashes
Hope this helps.