At just over your weight (158), same height (5'7"), I was about 10w higher than you (209?). That was the year I earned enough points to upgrade to Cat 2. I can't climb to save my life, nor can I TT, but I know tactics and I have good 20s power (approx 1100w on a good day, as I've figured out poring over power files).
Spin more - you can tax your aerobic system more and shift to bigger gears towards the end. I find that I spin until I blow and then I push.
In my best 20 min tests I've coasted or otherwise eased about 10 min in. After 10-20 seconds of going easy I manage to convince myself to keep going. Most of the time I fail to do that and I stop. I've completed maybe five 20 min FTP tests in 4 years and I probably started 30-40.
On the other hand my best 20 min effort came in those tests. My best efforts under 5m came in races. My best 60m also came in a race. But the 20m test, that's a testing thing, I never go as hard in a race as I did in my 20 min tests.
As a general rule I average 160-190w in most races. 200w and I am absolutely redlined. Most of my training is 140-160w avg. I've since downgraded to Cat 3 again and I can hold my own. In Cat 2 races I was usually in trouble except a big Cat 2 only race where I avg something like 170w until a crash on the last lap (Tour of Somerville). When I have to average 220w for any length of time I get shelled. Seems like 225w for 5 min is a max in a race, if it stays like that for 8-10 min I'm off the back.
Don't let your current FTP test hold you back. There are other things you can do, other ways to enjoy the bike. FTP and w/kg limit time trialing and climbing respectively. I score poorly in both so I focus on mass start stuff like flatter crits. Look on YouTube for sprinterdellacasa to see what a 200-210w FTP can do for you (2010 was my best year, the year I earned the points to upgrade to Cat 2).