Robert, 

Keep in mind that the highest lofted hybrid we have is 27*, which is roughly a 5 iron.  With the adjustability of these hybrids and the multiple iron models to choose from, I would recommend seeing a Club Fitter.  They will be able to provide you with the correct long game gapping, as well as finding the most playable iron model for your game. 

If you click on this link below it will take you to where you can search for Fitting Days and local Club Fitters.  Let me know if you have any further questions. 

http://www.titleist.com/find-a-golf-shop/

Cameron

1-888-TITLEIST 

Why not try driver, 4 wood (17) and 7 wood (21)?  A 4 wood is much more useful than a 15* 3 wood because you can launch it off more less than ideal lies.  The 7 wood will narrow the gap between it and the 4H to about 15 yards.  The 7W is also a little bit more workable vs a 5W because it is 1/2" shorter.

If you are a 4 handicap, you should be pretty adept at distance control (for instance shaving 10 yards off your distance for every 1/2" you choke down).  The niceity of 5H-7H is they are easy to work (I also don't have any difficulty drawing and fading either).

I've been playing an iron setup of 7-PW since 2006.  I found out that I couldn't hit anything above that very well when I started playing again in 2006.  I found a 7 wood and 5H to be a potent combo.   I also discovered "approach" (34 and 38*) hybrids in 2006-2008.  At one time I carried a G10 23-28-32H combination with a Snake Eyes 38H and used do it yourself 8-SW irons (was adapting to a swing change in 2009 and had trouble with 5-7 "transition" hollow body irons); I got my score consistently in the mid-high 80s with a setup of 1-4-7 woods, 28-32-38H, 8-SW, 60-64 SM2.  I started using a transition 7 iron at the end of 2009 and switched to a 34H in place of the 32 and 38.   I used my DIY irons until the end of 2010 and switched to Eye 2 irons. 

I currently carry TM Burner HT draw driver (13*) 44.5", 5/18 fww, 4-21 and 6-27 hybrids, AP1 7-PW and 4 Vokeys (50-54-58-62).  My reserve clubs are TM Burner 7W (I used that for a year and a half; I just acquired the 5W, 4 and 6H recently), SQ2 5/26 and 7/34 hybrids (used them up until getting the AP1s), Louisville Golf Niblick Even Stripe 10W and HL3 34 persimmon hybrids (I used the 10W between mid 2010-2011 and it was my go to 160 club before I got the SQ2; the 34 persimmon is more of a conversation piece on the golf course and, by the way, I can hit it 155 yards).   I've had my highest par count (10 out of 13 on an exec course) using the Burner HT driver and 7W, the Louisvilles, Eye 2 8-PW, Vokey 54-60-64 wedges and 7H putter (the only reason I had bogeys was I landed on the backs of two 155 yard par3s with the 34 and a pulled 7 wood).  Even now if I want to carry a "Sunday" bag, I can substitute the 7W and SQs for the 5W thru 7 iron.

When fitted as one set, the fitter can look at setting the 6 iron a little stronger if there is a wider gap between the 27 hybrid and the 6I.  I'm not sure you will need a 5H, unless your 165 is not consistent and not getting enough loft.  There may be some distance gain with the equivalent hybrid, but you should more expect the hybrid to gain more height and end up stopping shorterr for actually less distance including rollout.  My distance in the air is consistent from 6I to 5I, but more often the 5I will fly lower and I have to land short of the green to keep from going through.