ah, your questions are pretty subjective. i feel that a large part of your solution would have to be based on personal preference.
the technical advantage of using modules - cheaper way to have more synths, easier to carry etc but some people, such as myself for one, still feel more comfortable with a synth than a module by virtue of the operating interface. synth and module interfaces can be pretty different in some cases, e.g motif, PC2, triton. on the other hand, some other keyboardists are able to live with this.
not all, in fact few, synths have hammond drawbar modelling. the triton has a few, but those are merely crossfading between different samples, and not true drawbar simulation. probably the best hardware synth to get is the Nord Electro, which will cost u between 2 and 3k. or u could try the roland VR-760, or korg CX-3, all with drawbar action. software synths are great too - Native Instruments B4.
it also depends on how extreme u're prepared to go. the above-mentioned are very hammond-specialised synths. if u're prepared to compromise some and live with general ROMpler synths, the motif and EX series synths are great too, and maybe the kurzweil PC2. you should read up the harmony-central user reviews on the respective synths. i can say this much for now.
PS: i play a lot of piano and hammond too. i've got an EX5 synth which i'm very happy with, and am also running some software synths. the rehearsal studio i usually go to with my band provides an RS-50 synth, and i've found that to be marginally ok too.