Chef2 has got most of it.
DONT travel the Del. Bay in a SE or NW 'blow' .... not unusual to see 6ft. 'trochodial' (very steep, fast period) chop.
Going SE (down) start from the Engineers Cove at Chesapeake City on the C&D 2+ hours BEFORE flood/slack .... and ride the wave almost all the way down.
Going NW (up) try to cross Eph Shoal AT Cape Point at ebb/slack (throw a stone onto beach as you go) ... then angle to the shipping channel and ride the tide wave almost all the way 'up'.
If you can keep 6kts. (in slack water) you will enter the C&D on an inflowing tide/current ... and arrive at slack at Ches. City then to ride the backside 'wave' down the Ches. Use your tide/current tables (Eldridge, etc.) for 'good' planning when running the C&D + Delaware.
The current in the C&D is out-of-phase with the Del + Ches. tides ....
use the tide/current table info for the C&D PLUS the Del. River/Bay to plan your 'timing' .... gain an extra 2 to 2-1/2 kts SOG.
Either side of the ship channel is OK to run, few 'shallows'; especially on the NJ side of the ship channel is 'deeper'.
The Cohansey R. is a good 'hidey hole' but is very DEEP and has lots of current. When entering the Cohansey keep the GREEN outer marker to
STARBOARD !!!! ... run 'close' to the outer GREEN. The 'normal' portside-to-green when entering is becoming shoal especially towards the small island to the east of the entrance. Visually READ the water at the entrance.
Beware of heavy rains in the Pocono Mts. or in NE Penna. as it sometimes greatly affects the 'amount' of (current) water coming down the Del. River. Use Easton or Reigelsville as your 'benchmark' flow station to monitor:
Advanced Hydrologic Prediction Service: Philadelphia/Mount Holly click on the benchmark stations and then look at the MCFM value.
No need to follow the ship channel exactly ... you can cut the corner at the Salem Nuclear Station. Ship traffic has been unusually light on the Del. (& the Ches.) for the past few years. AIS (and or radar) is your friend if the visibility is low.
Fauna & Flora: GreenHeads are a spring/summer 'phenomenon' - get an 'electronic' fly-bat.
No-see-ums and other 'black flies' are equally bad in spring / early summer ..... DONT RUN YOUR ENGINE if there is NO wind and you are anchored, etc. !!!!!!!!
"Fuzzy head" midges emerge during the New Moon in spring thru early summer .... they will vomit a GREEN BLOB when then emerge and the GREEN is impossible to remove from sailcloth and will stain gelcoat - use your sail covers during such times. Fuzzy heads can contain/carry 'vibrio' (cholera).