What planetary combinations in a female birth chart indicate she will be loyal, caring and an ideal supporting wife?
Well placed Venus, 7th lord, and Jupiter will be the indicator of a loyal and caring wife
Who is an ideal wife(or husband) in the modern context?
The definition of loyal, ideal, and caring spouse is ever-changing. If you rewind back the history, women were restricted to speak in front of spouse. So a woman listening to a spouse without any disagreement was considered to be an ideal wife. Due to globalization, and industrialization woman are empowered today and started living independently in modern society. So the definition of an ideal spouse would be,
The ideal spouse is not the one who has the most commonality and one who listens to the spouse but one who understand and appreciate their difference of opinion between them.
The role of Venus
The Venus is the kalatra karaka ie: indicator of the spouse. If Venus gets benefic aspection or conjunction then the native will get a caring, understanding and loving spouse. If Venus gets afflicted by malefics then the spouse will be nagging, immatured and will always involve in conflicts.
The role of the 7th lord
The 7th house is the indicator of marriage and life partner. When 7th lord is well placed with benefic aspection then the spouse will be loyal, understanding and caring. The 9th lord conjoined with 7th lord without any affliction will give a righteous and loyal spouse. If Jupiter occupies the 7th house or conjoins the 7th lord without any affliction, then the spouse will be matured person and will become moral support to the husband.
Conclusion
When 7th lord and Venus are well placed with benefic aspection from Jupiter, Mercury, benefic 9th lord and well placed Moon the spouse will be loyal, loving, righteous and character of high moral standard.