the diversion route from the A28 is as easy as crossing Mathilde, if not easier, no traffic lights just dual carriageway and straight out onto the A13 if rejoining the A28 south.
only downside is an extra toll for 1 jct on the A29/A151/A150 route or as said above and continue a bit further to Yvetot/Pont Brotonne crossing, nice cross country route for a change with the option of non-toll route to pick up the 'old' N138.
From Le Havre i've always done non toll roads*, crossing at Tancarville and doing Pont Audemer / Orbec and down
* edited, original looked a bit mis-leading Toll-wise
