What I'd do:
-DSA815-TG SA/TG
I'd definitively get the SSA3021X after seeing Daves comparison between the two.
That Siglent is very tempting.
-DSG815 Signal generator
Nice unit, but given that you live in the US I'm sure you can get a good deal on an old (but better speced) HP RF generator or a Rohde and save some bucks.
I already have several older units.
HP 8640B signal generator fully restored.
IFR (AeroFlex) 1200 with spectrum analyzer.
IFR (AeroFlex) 1200 Super S with Spectrum and tracking gen.
-DS1054Z scope.
ok, no complaints here if 4 channels are needed. If you can live with 2 I'd buy the new siglent 200Mhz model, can't beat that price/performance.
I really love to have a four channel scope. Since 90 percent of my work and repairs are in the low band RF (0 to 30 MHz) repair/restore I believe this scope would do the job. Since it can be hacked to 100 MHz. I been using two Tektronix 2335 two channel 100 MHz scopes for years. Even with V/UHF I have been able to get by with 100 MHz scopes. I did buy a Owon PDS6062S a few years ago. Big mistake BTW.
I will say I like the looks of the Siglent. But the reason I like the Rigol is they have all three pieces same brand. Don't get me wrong my mind can change and I am always open to ideas. Appreciate the comment.