I'm so glad that these were raised again.
[I know I've given these chords in the thread referred to by T, but here is a refresher:]
Ending #1A nice & simple ending I should stop using now is the
#5 -> b7 -> 1.
(A simple way I look at it is that it's the whole tone scale from the sharp #5 to the 1 of the key you are playing in)
You use this ending as a sub for the generic 5-1
hint: you can play these chord as a simple major or M9,11 or 13- they all sound great.
say in Ab:
5 : Eb/G-Bb-Db-F [EbM9]
#5: E/ F#-G#-B-E [EM9]
b7: Gb/F-(Ab)-Bb-Db-(Eb) [GbM9,13]
1 : Ab/G-Ab-Bb-C-Eb [AbM9]
Re-iterate: the beauty of this is the liberty you have to extend the chords, so long as they remain major.
Ending #2
Another very very simple but nice ending i like is simply playing a minor 1 b2 chord as a passing chord/ filler between the 5-1, with the b2 as the bass note.
in Eb:
5 : Bb/Ab-C-D-F [5 chord as you want it]
b2: Fb/Gb-Bb-Eb [Ebm,b2 with b2 as bass (Ebm/E)]
1 : Eb/G-Bb-Eb [EbM]
[the way I always imagine the passing chord is that the bass is a #1 & I just flat the 3rd of the root chord in my RH]
Passing Chord #1 & 2These chord can be used interchangeably in the 1-4 progression if you want to avoid sounding monotonous. You will hear the 1st progression in many songs if you listen carefully
Chord # 1 in Bb:
1 : Bb-Bb/A-C-D-F [BbM9 but can be any major 1 chord]
b5: Fb /D-Gb-Ab-Bb [E9b5 , this = Dom9b5 chord of the b5 note of whatever key you're in]
4 : Eb/ D-Eb-G-Bb or Eb/D-G-C
Alternatively, you can play the major 3 chord to get to the 4. I hear this mostly in some jazz numbers but there are several hymns where I've heard it from.
Chord #2 in Bb:
1: Bb-Bb/A-C-D-F
3: D/A-Db-D-Gb
4: Eb/G-C-F [ or any major 4 chord]
With the chords given, you can play these with over 50% or more of the songs you play since they all have a 1-4 somewhere.
Another passing chord that I'm thinking of that fits the 1-4 is a b7:
in Bb:
as above, just play a major b7 chord between 1-4 [Ab/ Ab-C-Eb]
1 : Bb/A-C-D-F
b7: Ab/Ab-C-Eb
4 : Eb/G-C-D-(G)
(OK, just check if this sounds ok coz I'm just imagining it.)
Enjoy.