Hi Jean.
I have the same information as you do from Patrick & Isabel Quay forward. I think this part is pretty solid. I don't have parents for Jane Kewley, who married William Killip ca 1788. Do you have them?
Like you, I think the next generation back is Patrick & Christian Looney. You may be right about the 3 marriages of this Patrick, but it could be different Patricks. The 3 wills for a Patrick Killip on Brian Lawson's will index for 1689, 1705 and 1712 need to be checked, as it suggests 3 different people.
Kathrin Killip was bap 19 Feb 1681 (presumaby 1681/82) d of Patt Killip at Ballaugh. As the date is very close to John's 1682, I think one of these dates is a year out.
The IGI doesn't have a marriage for Patrick to Mary Cottier 1694. Do you have the detail? Brian's burial index has an entry for Mary Killip als Cottier at Lezayre 19 Feb 1724.
I found 7 of the 8 Patrick's you listed, but couldn't find the 1708 to John Killip & Isabel Stephen.
From IGI, here's my list up to 1801 of Patrick Killip baptisms:
1. 1627 Nov 30 to John Killip at Ballaugh
2. 1643 May 5 to Phillip Killip at Ballaugh
3. 1648 Mar 27 to Jon Killip at Ballaugh
4. 1677 Nov 20 to Wm Killip at Braddan
5. 1687 Jun 5 to Patrick & Christian Ballaugh
6. 1707 Feb 26 to James Killip & Maggy Spear
7. [your entry] 1708 to John Killip & Isabel Stephen
8. 1711 Aug 12 to John Killip Ballaugh
9. 1718 May 5 to Patrick Killip & Isabel Quay at Lonan
10. 1721 Oct 25 to Jon Killip Ballaugh
11. 1722 Mar 10 to Wm Killip Ballaugh
12. 1730 Dec 29 to John Killip Ballaugh
13. 1748 30 Oct to Patrick Killip & Jane Kermode Ballaugh
14. 1758 26 Feb to Pat Killip & sarah Taylor Kirk German (d infant)
15. 1760 May 15 too Robt Killip & Jane Corkil Lezayre
16. 1776 26 Jul to Wm Killip & Margt Kewley Ballaugh
17. 1777 6 Apr to William Killip & Mary Cowley
18. 1784 11 May to John Killip & Jane Lawson Lonan
19. 1786 Feb 27 to Paul Killlip & Elr Mylvorrey Ballaugh
20. 1801 Dec 22 to Thos Killip & Margt Caley Lezayre
There are a handful of Killip baptisms to a Patrick Killip at Ballaugh for dates well before 1677, so there must have been an earlier generation Patrick.
I hope this will help.
Eric