You've actually got plenty of options worth considering, but also to address a few things you mentioned:
1. Shutter lag is fortunately simply not an issue on any DSLR nowadays, regardless of brand. They're all instant, more or less, with the delays coming more from various settings, autofocus needs, etc. For someone looking for a more 'classic' manual shooting style, no worries!
2. The good thing about the DSLRs and all their complex options is that you don't have to use them. All DSLRs from all brands have manual functionality that can be as simple as your old Minolta - the exception being where the aperture control is located (usually on the camera rather than on the lens). But setting it is no more complex than before.
3. Micro 4:3 and Sony NEX cameras are an option - consider a few things for these - the experience has the ability to be even MORE traditional than a DSLR in feel for a manual shooter in some respects, while being much more clearly 'digital' in other respects. The 'more' traditional feel can come when using old manual lenses with these cameras - both M4:3 and NEX cameras can take any manual lens, any mount, any brand via simple spacer adapters...when paired with these, the manual shooter can find the shooting experience very much like a classic SLR, in that you are using the aperture ring on the lens to set aperture, the focus control on the lens to dial in the focus, and the jog wheel on the camera to adjust the shutter speed. However, the difference with these cameras is that you are using a live view based system, seeing the image on either an electronic viewfinder or LCD screen rather than a TTL OVF. So that's the one respect where these cameras may feel more digital. However, used with manual lenses and in manual mode, they can fire with as little lag as any DSLR.
4. Do you still have your Minolta lenses? If yes, this might be a decent reason to consider the NEX or M4:3 option, as you would be able to buy a simple $20 adapter and continue to use all your lenses. Going to a DSLR, your lenses won't be compatible with any current system, with even the Sony bodies (which use Minolta's A mount) are not compatible with Minolta's older MD mount.
Sony DSLR-A580 / Sony 18-250mm / Minolta 50mm F1.7 / Sigma 30mm F1.4 / Tamron 10-24mm / Tamron 150-600mm / Tamron 90mm F2.8 macro / Minolta 300mm F4 APO
Sony A6000 / 18-55mm F3.5-5.6 / 55-210mm F4-6.3 / 10-18mm F4 / 35mm F1.8 / 16mm F2.8 / via manual adapter, lots of Pentax K mount, Konica K/AR mount, and Leica M mount manual lenses