7 Segment LED display for Photovoltaic plant - GENERAL

Hello
I am looking at tips on circuits and components for my PV display 
project. I do not have a specific preference for PICs or microcontrolers 
of any specific type.


I would like to build a Display panel for my Photovoltaic generator. The 
display contains a mask with the fixed text and cut-out slots in the 
mask where the LED elements will be placed (6 slots with 3-6 digits). I 
have a pulse input (for example 20 pulses pro kW) from a power-meter 
that registers the force produced by the PV inverter. Based on the 
pulse, I need to derive and display the following:

-electrical force delivered at present: (Calculated on base of the time 
difference betwween 2 pulses)

-force delivered for the day
-total force delivered from the start (installation date)


The functions I am looking for:

- computing force delivered and counters (daily, total)
- adjusting the pulse/kW ratio
- driving a 7 Segment LED (High power LEDs visible in daylight)
- small control panel for setting the values


nice to have:

- LED brightness controled by external light intensity and swiched off 
at night
- Ethernet and/or RS485  interface to read out current values and set 
counters througn the local LAN or RS485 bus.
- if there is a power failure the initial value of the counters have to 
be read/set from an external source.
- low current consumption (except LEDs)
- isolated input for pulses.
- ability to duplicate the values on a seccond remote display (RS485?)

I would appreciate any tips a the basic components to use. Price is not 
(within limits) a primary factor. More important is the functionality 
and future extensions (Display of date, temperature etc.) The prefered 
way for me would be a development kit, which contains at least the basic 
components required. My experience is limited to "decrete components 
electronics" and commercial programming.