Here are some variations that you may add to Surya Namaskar. These variations should be placed between the Adho Mukha Svanasana. Be sure to have some blocks and a blanket at hand. When doing the arm balances you may want a blanket incase you loose balance.
When doing any twists, be sure to start the twist from the waist. Then move upwards.
1. Sukasana Twist, Ardha Maricyasana 3 & Urdhva Mukha Svanasana
2. Malasana (Garland), Virasana (Hero) & Urdhva Mukha Svanasana
3. Bakasana, Ardha Matsyendrasana I & Urdhva Mukha Svanasana
4. Parsva Bakasana, Bharadvajasana I & Urdhva Mukha Svanasana
5. Lolasana, Gomukasana & Urdhva Mukha Svanasana
6. Lolasana, Janu Sirsasana & Urdhva Mukha Svanasana
7. Parsva Bakasana, Ardha Baddha Padma Pascimottanasana (leg in lotus) & Urdhva Mukha Svanasana
8. Bakasana, Triang Mukhaikapada Pascimottanasana (one heel by the hip) & Urdhva Mukha Svanasana
9. Lolasana, Maricyasana I & Urdhva Mukha Svanasana
10. Lolasana, Pascimottanasana & Urdhva Mukha Svanasana